Question: What are codons?

Answer: a series of three-nucleotide sequences

The expression of genes encoded in DNA begins by transcribing the gene into RNA, a second type of nucleic acid that is very similar to DNA, but whose monomers contain the sugar ribose rather than deoxyribose. RNA also contains the base uracil in place of thymine. RNA molecules are less stable than DNA and are typically single-stranded. <hl> Genes that encode proteins are composed of a series of three-nucleotide sequences called codons, which serve as the "words" in the genetic "language". <hl> The genetic code specifies the correspondence during protein translation between codons and amino acids. The genetic code is nearly the same for all known organisms.:4.1

The expression of genes encoded in DNA begins by transcribing the gene into RNA, a second type of nucleic acid that is very similar to DNA, but whose monomers contain the sugar ribose rather than deoxyribose. RNA also contains the base uracil in place of thymine. RNA molecules are less stable than DNA and are typically single-stranded. Genes that encode proteins are composed of <hl> a series of three-nucleotide sequences <hl> called codons, which serve as the "words" in the genetic "language". The genetic code specifies the correspondence during protein translation between codons and amino acids. The genetic code is nearly the same for all known organisms.:4.1


Question: What specifies the correspondence between codons and amino acids during protein translation?

The expression of genes encoded in DNA begins by transcribing the gene into RNA, a second type of nucleic acid that is very similar to DNA, but whose monomers contain the sugar ribose rather than deoxyribose. RNA also contains the base uracil in place of thymine. RNA molecules are less stable than DNA and are typically single-stranded. Genes that encode proteins are composed of a series of three-nucleotide sequences called codons, which serve as the "words" in the genetic "language". The genetic code specifies the correspondence during protein translation between codons and amino acids. The genetic code is nearly the same for all known organisms.:4.1

Answer: The genetic code

The expression of genes encoded in DNA begins by transcribing the gene into RNA, a second type of nucleic acid that is very similar to DNA, but whose monomers contain the sugar ribose rather than deoxyribose. RNA also contains the base uracil in place of thymine. RNA molecules are less stable than DNA and are typically single-stranded. Genes that encode proteins are composed of a series of three-nucleotide sequences called codons, which serve as the "words" in the genetic "language". <hl> The genetic code specifies the correspondence during protein translation between codons and amino acids. <hl> The genetic code is nearly the same for all known organisms.:4.1

The expression of genes encoded in DNA begins by transcribing the gene into RNA, a second type of nucleic acid that is very similar to DNA, but whose monomers contain the sugar ribose rather than deoxyribose. RNA also contains the base uracil in place of thymine. RNA molecules are less stable than DNA and are typically single-stranded. Genes that encode proteins are composed of a series of three-nucleotide sequences called codons, which serve as the "words" in the genetic "language". <hl> The genetic code <hl> specifies the correspondence during protein translation between codons and amino acids. The genetic code is nearly the same for all known organisms.:4.1


Question: What is the total complement of genes in an organism or cell known as?

The total complement of genes in an organism or cell is known as its genome, which may be stored on one or more chromosomes. A chromosome consists of a single, very long DNA helix on which thousands of genes are encoded.:4.2 The region of the chromosome at which a particular gene is located is called its locus. Each locus contains one allele of a gene; however, members of a population may have different alleles at the locus, each with a slightly different gene sequence.

Answer: its genome

<hl> The total complement of genes in an organism or cell is known as its genome , which may be stored on one or more chromosomes. <hl> A chromosome consists of a single, very long DNA helix on which thousands of genes are encoded.:4.2 The region of the chromosome at which a particular gene is located is called its locus. Each locus contains one allele of a gene; however, members of a population may have different alleles at the locus, each with a slightly different gene sequence.

The total complement of genes in an organism or cell is known as <hl> its genome <hl>, which may be stored on one or more chromosomes. A chromosome consists of a single, very long DNA helix on which thousands of genes are encoded.:4.2 The region of the chromosome at which a particular gene is located is called its locus. Each locus contains one allele of a gene; however, members of a population may have different alleles at the locus, each with a slightly different gene sequence.

The total complement of genes in an organism or cell is known as <hl> its genome <hl> , which may be stored on one or more chromosomes.


Question: What does a chromosome consist of?

Answer: a single, very long DNA helix

The total complement of genes in an organism or cell is known as its genome, which may be stored on one or more chromosomes. <hl> A chromosome consists of a single, very long DNA helix on which thousands of genes are encoded.:4.2 <hl> The region of the chromosome at which a particular gene is located is called its locus. Each locus contains one allele of a gene; however, members of a population may have different alleles at the locus, each with a slightly different gene sequence.

The total complement of genes in an organism or cell is known as its genome, which may be stored on one or more chromosomes. A chromosome consists of <hl> a single, very long DNA helix <hl> on which thousands of genes are encoded.:4.2 The region of the chromosome at which a particular gene is located is called its locus. Each locus contains one allele of a gene; however, members of a population may have different alleles at the locus, each with a slightly different gene sequence.


Question: What is encoded on a chromosome?

Answer: thousands of genes

The total complement of genes in an organism or cell is known as its genome, which may be stored on one or more chromosomes. <hl> A chromosome consists of a single, very long DNA helix on which thousands of genes are encoded.:4.2 <hl> The region of the chromosome at which a particular gene is located is called its locus. Each locus contains one allele of a gene; however, members of a population may have different alleles at the locus, each with a slightly different gene sequence.

The total complement of genes in an organism or cell is known as its genome, which may be stored on one or more chromosomes. A chromosome consists of a single, very long DNA helix on which <hl> thousands of genes <hl> are encoded.:4.2 The region of the chromosome at which a particular gene is located is called its locus. Each locus contains one allele of a gene; however, members of a population may have different alleles at the locus, each with a slightly different gene sequence.


Question: What is the region of the chromosome at which a particular gene is located called?

Answer: its locus

The total complement of genes in an organism or cell is known as its genome, which may be stored on one or more chromosomes. A chromosome consists of a single, very long DNA helix on which thousands of genes are encoded.:4.2 <hl> The region of the chromosome at which a particular gene is located is called its locus . <hl> Each locus contains one allele of a gene; however, members of a population may have different alleles at the locus, each with a slightly different gene sequence.

The total complement of genes in an organism or cell is known as its genome, which may be stored on one or more chromosomes. A chromosome consists of a single, very long DNA helix on which thousands of genes are encoded.:4.2 The region of the chromosome at which a particular gene is located is called <hl> its locus <hl>. Each locus contains one allele of a gene; however, members of a population may have different alleles at the locus, each with a slightly different gene sequence.

The region of the chromosome at which a particular gene is located is called <hl> its locus <hl> .


Question: What does each locus contain?

Answer: one allele of a gene

The total complement of genes in an organism or cell is known as its genome, which may be stored on one or more chromosomes. A chromosome consists of a single, very long DNA helix on which thousands of genes are encoded.:4.2 The region of the chromosome at which a particular gene is located is called its locus. <hl> Each locus contains one allele of a gene ; however, members of a population may have different alleles at the locus, each with a slightly different gene sequence. <hl>

The total complement of genes in an organism or cell is known as its genome, which may be stored on one or more chromosomes. A chromosome consists of a single, very long DNA helix on which thousands of genes are encoded.:4.2 The region of the chromosome at which a particular gene is located is called its locus. Each locus contains <hl> one allele of a gene <hl>; however, members of a population may have different alleles at the locus, each with a slightly different gene sequence.

Each locus contains <hl> one allele of a gene <hl> ; however, members of a population may have different alleles at the locus, each with a slightly different gene sequence.


Question: Where are the majority of eukaryotic genes stored?

The majority of eukaryotic genes are stored on a set of large, linear chromosomes. The chromosomes are packed within the nucleus in complex with storage proteins called histones to form a unit called a nucleosome. DNA packaged and condensed in this way is called chromatin.:4.2 The manner in which DNA is stored on the histones, as well as chemical modifications of the histone itself, regulate whether a particular region of DNA is accessible for gene expression. In addition to genes, eukaryotic chromosomes contain sequences involved in ensuring that the DNA is copied without degradation of end regions and sorted into daughter cells during cell division: replication origins, telomeres and the centromere.:4.2 Replication origins are the sequence regions where DNA replication is initiated to make two copies of the chromosome. Telomeres are long stretches of repetitive sequence that cap the ends of the linear chromosomes and prevent degradation of coding and regulatory regions during DNA replication. The length of the telomeres decreases each time the genome is replicated and has been implicated in the aging process. The centromere is required for binding spindle fibres to separate sister chromatids into daughter cells during cell division.:18.2

Answer: on a set of large, linear chromosomes

<hl> The majority of eukaryotic genes are stored on a set of large, linear chromosomes . <hl> The chromosomes are packed within the nucleus in complex with storage proteins called histones to form a unit called a nucleosome. DNA packaged and condensed in this way is called chromatin.:4.2 The manner in which DNA is stored on the histones, as well as chemical modifications of the histone itself, regulate whether a particular region of DNA is accessible for gene expression. In addition to genes, eukaryotic chromosomes contain sequences involved in ensuring that the DNA is copied without degradation of end regions and sorted into daughter cells during cell division: replication origins, telomeres and the centromere.:4.2 Replication origins are the sequence regions where DNA replication is initiated to make two copies of the chromosome. Telomeres are long stretches of repetitive sequence that cap the ends of the linear chromosomes and prevent degradation of coding and regulatory regions during DNA replication. The length of the telomeres decreases each time the genome is replicated and has been implicated in the aging process. The centromere is required for binding spindle fibres to separate sister chromatids into daughter cells during cell division.:18.2

The majority of eukaryotic genes are stored <hl> on a set of large, linear chromosomes <hl>. The chromosomes are packed within the nucleus in complex with storage proteins called histones to form a unit called a nucleosome. DNA packaged and condensed in this way is called chromatin.:4.2 The manner in which DNA is stored on the histones, as well as chemical modifications of the histone itself, regulate whether a particular region of DNA is accessible for gene expression. In addition to genes, eukaryotic chromosomes contain sequences involved in ensuring that the DNA is copied without degradation of end regions and sorted into daughter cells during cell division: replication origins, telomeres and the centromere.:4.2 Replication origins are the sequence regions where DNA replication is initiated to make two copies of the chromosome. Telomeres are long stretches of repetitive sequence that cap the ends of the linear chromosomes and prevent degradation of coding and regulatory regions during DNA replication. The length of the telomeres decreases each time the genome is replicated and has been implicated in the aging process. The centromere is required for binding spindle fibres to separate sister chromatids into daughter cells during cell division.:18.2

The majority of eukaryotic genes are stored <hl> on a set of large, linear chromosomes <hl> .


Question: Chromosomes that are packed within the nucleus in complex with histones are called what?

Answer: a nucleosome

The majority of eukaryotic genes are stored on a set of large, linear chromosomes. <hl> The chromosomes are packed within the nucleus in complex with storage proteins called histones to form a unit called a nucleosome . <hl> DNA packaged and condensed in this way is called chromatin.:4.2 The manner in which DNA is stored on the histones, as well as chemical modifications of the histone itself, regulate whether a particular region of DNA is accessible for gene expression. In addition to genes, eukaryotic chromosomes contain sequences involved in ensuring that the DNA is copied without degradation of end regions and sorted into daughter cells during cell division: replication origins, telomeres and the centromere.:4.2 Replication origins are the sequence regions where DNA replication is initiated to make two copies of the chromosome. Telomeres are long stretches of repetitive sequence that cap the ends of the linear chromosomes and prevent degradation of coding and regulatory regions during DNA replication. The length of the telomeres decreases each time the genome is replicated and has been implicated in the aging process. The centromere is required for binding spindle fibres to separate sister chromatids into daughter cells during cell division.:18.2

The majority of eukaryotic genes are stored on a set of large, linear chromosomes. The chromosomes are packed within the nucleus in complex with storage proteins called histones to form a unit called <hl> a nucleosome <hl>. DNA packaged and condensed in this way is called chromatin.:4.2 The manner in which DNA is stored on the histones, as well as chemical modifications of the histone itself, regulate whether a particular region of DNA is accessible for gene expression. In addition to genes, eukaryotic chromosomes contain sequences involved in ensuring that the DNA is copied without degradation of end regions and sorted into daughter cells during cell division: replication origins, telomeres and the centromere.:4.2 Replication origins are the sequence regions where DNA replication is initiated to make two copies of the chromosome. Telomeres are long stretches of repetitive sequence that cap the ends of the linear chromosomes and prevent degradation of coding and regulatory regions during DNA replication. The length of the telomeres decreases each time the genome is replicated and has been implicated in the aging process. The centromere is required for binding spindle fibres to separate sister chromatids into daughter cells during cell division.:18.2

The chromosomes are packed within the nucleus in complex with storage proteins called histones to form a unit called <hl> a nucleosome <hl> .


Question: What does the manner of DNA storage on the histone and the chemical modifications of the histone itself regulate?

Answer: whether a particular region of DNA is accessible for gene expression

The majority of eukaryotic genes are stored on a set of large, linear chromosomes. The chromosomes are packed within the nucleus in complex with storage proteins called histones to form a unit called a nucleosome. DNA packaged and condensed in this way is called chromatin.:4.2 <hl> The manner in which DNA is stored on the histones, as well as chemical modifications of the histone itself, regulate whether a particular region of DNA is accessible for gene expression . <hl> In addition to genes, eukaryotic chromosomes contain sequences involved in ensuring that the DNA is copied without degradation of end regions and sorted into daughter cells during cell division: replication origins, telomeres and the centromere.:4.2 Replication origins are the sequence regions where DNA replication is initiated to make two copies of the chromosome. Telomeres are long stretches of repetitive sequence that cap the ends of the linear chromosomes and prevent degradation of coding and regulatory regions during DNA replication. The length of the telomeres decreases each time the genome is replicated and has been implicated in the aging process. The centromere is required for binding spindle fibres to separate sister chromatids into daughter cells during cell division.:18.2

The majority of eukaryotic genes are stored on a set of large, linear chromosomes. The chromosomes are packed within the nucleus in complex with storage proteins called histones to form a unit called a nucleosome. DNA packaged and condensed in this way is called chromatin.:4.2 The manner in which DNA is stored on the histones, as well as chemical modifications of the histone itself, regulate <hl> whether a particular region of DNA is accessible for gene expression <hl>. In addition to genes, eukaryotic chromosomes contain sequences involved in ensuring that the DNA is copied without degradation of end regions and sorted into daughter cells during cell division: replication origins, telomeres and the centromere.:4.2 Replication origins are the sequence regions where DNA replication is initiated to make two copies of the chromosome. Telomeres are long stretches of repetitive sequence that cap the ends of the linear chromosomes and prevent degradation of coding and regulatory regions during DNA replication. The length of the telomeres decreases each time the genome is replicated and has been implicated in the aging process. The centromere is required for binding spindle fibres to separate sister chromatids into daughter cells during cell division.:18.2

The manner in which DNA is stored on the histones, as well as chemical modifications of the histone itself, regulate <hl> whether a particular region of DNA is accessible for gene expression <hl> .


Question: What are replication origins?

Answer: regions where DNA replication is initiated to make two copies of the chromosome

The majority of eukaryotic genes are stored on a set of large, linear chromosomes. The chromosomes are packed within the nucleus in complex with storage proteins called histones to form a unit called a nucleosome. DNA packaged and condensed in this way is called chromatin.:4.2 The manner in which DNA is stored on the histones, as well as chemical modifications of the histone itself, regulate whether a particular region of DNA is accessible for gene expression. <hl> In addition to genes, eukaryotic chromosomes contain sequences involved in ensuring that the DNA is copied without degradation of end regions and sorted into daughter cells during cell division: replication origins, telomeres and the centromere.:4.2 Replication origins are the sequence regions where DNA replication is initiated to make two copies of the chromosome . <hl> Telomeres are long stretches of repetitive sequence that cap the ends of the linear chromosomes and prevent degradation of coding and regulatory regions during DNA replication. The length of the telomeres decreases each time the genome is replicated and has been implicated in the aging process. The centromere is required for binding spindle fibres to separate sister chromatids into daughter cells during cell division.:18.2

The majority of eukaryotic genes are stored on a set of large, linear chromosomes. The chromosomes are packed within the nucleus in complex with storage proteins called histones to form a unit called a nucleosome. DNA packaged and condensed in this way is called chromatin.:4.2 The manner in which DNA is stored on the histones, as well as chemical modifications of the histone itself, regulate whether a particular region of DNA is accessible for gene expression. In addition to genes, eukaryotic chromosomes contain sequences involved in ensuring that the DNA is copied without degradation of end regions and sorted into daughter cells during cell division: replication origins, telomeres and the centromere.:4.2 Replication origins are the sequence <hl> regions where DNA replication is initiated to make two copies of the chromosome <hl>. Telomeres are long stretches of repetitive sequence that cap the ends of the linear chromosomes and prevent degradation of coding and regulatory regions during DNA replication. The length of the telomeres decreases each time the genome is replicated and has been implicated in the aging process. The centromere is required for binding spindle fibres to separate sister chromatids into daughter cells during cell division.:18.2

In addition to genes, eukaryotic chromosomes contain sequences involved in ensuring that the DNA is copied without degradation of end regions and sorted into daughter cells during cell division: replication origins, telomeres and the centromere.:4.2 Replication origins are the sequence <hl> regions where DNA replication is initiated to make two copies of the chromosome <hl> .


Question: Long stretches of repetitive sequence that cap the ends of the linear chromosomes are called what?

Answer: Telomeres

The majority of eukaryotic genes are stored on a set of large, linear chromosomes. The chromosomes are packed within the nucleus in complex with storage proteins called histones to form a unit called a nucleosome. DNA packaged and condensed in this way is called chromatin.:4.2 The manner in which DNA is stored on the histones, as well as chemical modifications of the histone itself, regulate whether a particular region of DNA is accessible for gene expression. In addition to genes, eukaryotic chromosomes contain sequences involved in ensuring that the DNA is copied without degradation of end regions and sorted into daughter cells during cell division: replication origins, telomeres and the centromere.:4.2 Replication origins are the sequence regions where DNA replication is initiated to make two copies of the chromosome. <hl> Telomeres are long stretches of repetitive sequence that cap the ends of the linear chromosomes and prevent degradation of coding and regulatory regions during DNA replication. <hl> The length of the telomeres decreases each time the genome is replicated and has been implicated in the aging process. The centromere is required for binding spindle fibres to separate sister chromatids into daughter cells during cell division.:18.2

The majority of eukaryotic genes are stored on a set of large, linear chromosomes. The chromosomes are packed within the nucleus in complex with storage proteins called histones to form a unit called a nucleosome. DNA packaged and condensed in this way is called chromatin.:4.2 The manner in which DNA is stored on the histones, as well as chemical modifications of the histone itself, regulate whether a particular region of DNA is accessible for gene expression. In addition to genes, eukaryotic chromosomes contain sequences involved in ensuring that the DNA is copied without degradation of end regions and sorted into daughter cells during cell division: replication origins, telomeres and the centromere.:4.2 Replication origins are the sequence regions where DNA replication is initiated to make two copies of the chromosome. <hl> Telomeres <hl> are long stretches of repetitive sequence that cap the ends of the linear chromosomes and prevent degradation of coding and regulatory regions during DNA replication. The length of the telomeres decreases each time the genome is replicated and has been implicated in the aging process. The centromere is required for binding spindle fibres to separate sister chromatids into daughter cells during cell division.:18.2


Question: What are prokaryotes?

Prokaryotes (bacteria and archaea) typically store their genomes on a single large, circular chromosome. Similarly, some eukaryotic organelles contain a remnant circular chromosome with a small number of genes.:14.4 Prokaryotes sometimes supplement their chromosome with additional small circles of DNA called plasmids, which usually encode only a few genes and are transferable between individuals. For example, the genes for antibiotic resistance are usually encoded on bacterial plasmids and can be passed between individual cells, even those of different species, via horizontal gene transfer.

Answer: bacteria and archaea

<hl> Prokaryotes ( bacteria and archaea ) typically store their genomes on a single large, circular chromosome. <hl> Similarly, some eukaryotic organelles contain a remnant circular chromosome with a small number of genes.:14.4 Prokaryotes sometimes supplement their chromosome with additional small circles of DNA called plasmids, which usually encode only a few genes and are transferable between individuals. For example, the genes for antibiotic resistance are usually encoded on bacterial plasmids and can be passed between individual cells, even those of different species, via horizontal gene transfer.

Prokaryotes (<hl> bacteria and archaea <hl>) typically store their genomes on a single large, circular chromosome. Similarly, some eukaryotic organelles contain a remnant circular chromosome with a small number of genes.:14.4 Prokaryotes sometimes supplement their chromosome with additional small circles of DNA called plasmids, which usually encode only a few genes and are transferable between individuals. For example, the genes for antibiotic resistance are usually encoded on bacterial plasmids and can be passed between individual cells, even those of different species, via horizontal gene transfer.

Prokaryotes ( <hl> bacteria and archaea <hl> ) typically store their genomes on a single large, circular chromosome.


Question: How do prokaryotes store their genomes?

Answer: on a single large, circular chromosome

<hl> Prokaryotes (bacteria and archaea) typically store their genomes on a single large, circular chromosome . <hl> Similarly, some eukaryotic organelles contain a remnant circular chromosome with a small number of genes.:14.4 Prokaryotes sometimes supplement their chromosome with additional small circles of DNA called plasmids, which usually encode only a few genes and are transferable between individuals. For example, the genes for antibiotic resistance are usually encoded on bacterial plasmids and can be passed between individual cells, even those of different species, via horizontal gene transfer.

Prokaryotes (bacteria and archaea) typically store their genomes <hl> on a single large, circular chromosome <hl>. Similarly, some eukaryotic organelles contain a remnant circular chromosome with a small number of genes.:14.4 Prokaryotes sometimes supplement their chromosome with additional small circles of DNA called plasmids, which usually encode only a few genes and are transferable between individuals. For example, the genes for antibiotic resistance are usually encoded on bacterial plasmids and can be passed between individual cells, even those of different species, via horizontal gene transfer.

Prokaryotes (bacteria and archaea) typically store their genomes <hl> on a single large, circular chromosome <hl> .


Question: What type of chromosome do some eukaryotic organelles contain?

Answer: a remnant circular chromosome with a small number of genes

Prokaryotes (bacteria and archaea) typically store their genomes on a single large, circular chromosome. <hl> Similarly, some eukaryotic organelles contain a remnant circular chromosome with a small number of genes .:14.4 Prokaryotes sometimes supplement their chromosome with additional small circles of DNA called plasmids, which usually encode only a few genes and are transferable between individuals. <hl> For example, the genes for antibiotic resistance are usually encoded on bacterial plasmids and can be passed between individual cells, even those of different species, via horizontal gene transfer.

Prokaryotes (bacteria and archaea) typically store their genomes on a single large, circular chromosome. Similarly, some eukaryotic organelles contain <hl> a remnant circular chromosome with a small number of genes <hl>.:14.4 Prokaryotes sometimes supplement their chromosome with additional small circles of DNA called plasmids, which usually encode only a few genes and are transferable between individuals. For example, the genes for antibiotic resistance are usually encoded on bacterial plasmids and can be passed between individual cells, even those of different species, via horizontal gene transfer.

Similarly, some eukaryotic organelles contain <hl> a remnant circular chromosome with a small number of genes <hl> .:14.4 Prokaryotes sometimes supplement their chromosome with additional small circles of DNA called plasmids, which usually encode only a few genes and are transferable between individuals.


Question: Small circles of DNA that encode only a few genes and are transferable between individuals are called what?

Answer: plasmids

Prokaryotes (bacteria and archaea) typically store their genomes on a single large, circular chromosome. <hl> Similarly, some eukaryotic organelles contain a remnant circular chromosome with a small number of genes.:14.4 Prokaryotes sometimes supplement their chromosome with additional small circles of DNA called plasmids , which usually encode only a few genes and are transferable between individuals. <hl> For example, the genes for antibiotic resistance are usually encoded on bacterial plasmids and can be passed between individual cells, even those of different species, via horizontal gene transfer.

Prokaryotes (bacteria and archaea) typically store their genomes on a single large, circular chromosome. Similarly, some eukaryotic organelles contain a remnant circular chromosome with a small number of genes.:14.4 Prokaryotes sometimes supplement their chromosome with additional small circles of DNA called <hl> plasmids <hl>, which usually encode only a few genes and are transferable between individuals. For example, the genes for antibiotic resistance are usually encoded on bacterial plasmids and can be passed between individual cells, even those of different species, via horizontal gene transfer.

Similarly, some eukaryotic organelles contain a remnant circular chromosome with a small number of genes.:14.4 Prokaryotes sometimes supplement their chromosome with additional small circles of DNA called <hl> plasmids <hl> , which usually encode only a few genes and are transferable between individuals.


Question: What allows genes for antibiotic resistance to be passed between individual cells?

Answer: horizontal gene transfer

Prokaryotes (bacteria and archaea) typically store their genomes on a single large, circular chromosome. Similarly, some eukaryotic organelles contain a remnant circular chromosome with a small number of genes.:14.4 Prokaryotes sometimes supplement their chromosome with additional small circles of DNA called plasmids, which usually encode only a few genes and are transferable between individuals. <hl> For example, the genes for antibiotic resistance are usually encoded on bacterial plasmids and can be passed between individual cells, even those of different species, via horizontal gene transfer . <hl>

Prokaryotes (bacteria and archaea) typically store their genomes on a single large, circular chromosome. Similarly, some eukaryotic organelles contain a remnant circular chromosome with a small number of genes.:14.4 Prokaryotes sometimes supplement their chromosome with additional small circles of DNA called plasmids, which usually encode only a few genes and are transferable between individuals. For example, the genes for antibiotic resistance are usually encoded on bacterial plasmids and can be passed between individual cells, even those of different species, via <hl> horizontal gene transfer <hl>.

For example, the genes for antibiotic resistance are usually encoded on bacterial plasmids and can be passed between individual cells, even those of different species, via <hl> horizontal gene transfer <hl> .


Question: What type of organism has relatively gene dense chromosomes?

Whereas the chromosomes of prokaryotes are relatively gene-dense, those of eukaryotes often contain regions of DNA that serve no obvious function. Simple single-celled eukaryotes have relatively small amounts of such DNA, whereas the genomes of complex multicellular organisms, including humans, contain an absolute majority of DNA without an identified function. This DNA has often been referred to as "junk DNA". However, more recent analyses suggest that, although protein-coding DNA makes up barely 2% of the human genome, about 80% of the bases in the genome may be expressed, so the term "junk DNA" may be a misnomer.

Answer: prokaryotes

<hl> Whereas the chromosomes of prokaryotes are relatively gene-dense, those of eukaryotes often contain regions of DNA that serve no obvious function. <hl> Simple single-celled eukaryotes have relatively small amounts of such DNA, whereas the genomes of complex multicellular organisms, including humans, contain an absolute majority of DNA without an identified function. This DNA has often been referred to as "junk DNA". However, more recent analyses suggest that, although protein-coding DNA makes up barely 2% of the human genome, about 80% of the bases in the genome may be expressed, so the term "junk DNA" may be a misnomer.

Whereas the chromosomes of <hl> prokaryotes <hl> are relatively gene-dense, those of eukaryotes often contain regions of DNA that serve no obvious function. Simple single-celled eukaryotes have relatively small amounts of such DNA, whereas the genomes of complex multicellular organisms, including humans, contain an absolute majority of DNA without an identified function. This DNA has often been referred to as "junk DNA". However, more recent analyses suggest that, although protein-coding DNA makes up barely 2% of the human genome, about 80% of the bases in the genome may be expressed, so the term "junk DNA" may be a misnomer.


Question: Regions of DNA that serve no obvious function are often found in what type of organism?

Answer: eukaryotes

<hl> Whereas the chromosomes of prokaryotes are relatively gene-dense, those of eukaryotes often contain regions of DNA that serve no obvious function. <hl> Simple single-celled eukaryotes have relatively small amounts of such DNA, whereas the genomes of complex multicellular organisms, including humans, contain an absolute majority of DNA without an identified function. This DNA has often been referred to as "junk DNA". However, more recent analyses suggest that, although protein-coding DNA makes up barely 2% of the human genome, about 80% of the bases in the genome may be expressed, so the term "junk DNA" may be a misnomer.

Whereas the chromosomes of prokaryotes are relatively gene-dense, those of <hl> eukaryotes <hl> often contain regions of DNA that serve no obvious function. Simple single-celled eukaryotes have relatively small amounts of such DNA, whereas the genomes of complex multicellular organisms, including humans, contain an absolute majority of DNA without an identified function. This DNA has often been referred to as "junk DNA". However, more recent analyses suggest that, although protein-coding DNA makes up barely 2% of the human genome, about 80% of the bases in the genome may be expressed, so the term "junk DNA" may be a misnomer.


Question: What is referred to as "junk DNA"?

Answer: DNA without an identified function

Whereas the chromosomes of prokaryotes are relatively gene-dense, those of eukaryotes often contain regions of DNA that serve no obvious function. <hl> Simple single-celled eukaryotes have relatively small amounts of such DNA, whereas the genomes of complex multicellular organisms, including humans, contain an absolute majority of DNA without an identified function . <hl> This DNA has often been referred to as "junk DNA". However, more recent analyses suggest that, although protein-coding DNA makes up barely 2% of the human genome, about 80% of the bases in the genome may be expressed, so the term "junk DNA" may be a misnomer.

Whereas the chromosomes of prokaryotes are relatively gene-dense, those of eukaryotes often contain regions of DNA that serve no obvious function. Simple single-celled eukaryotes have relatively small amounts of such DNA, whereas the genomes of complex multicellular organisms, including humans, contain an absolute majority of <hl> DNA without an identified function <hl>. This DNA has often been referred to as "junk DNA". However, more recent analyses suggest that, although protein-coding DNA makes up barely 2% of the human genome, about 80% of the bases in the genome may be expressed, so the term "junk DNA" may be a misnomer.

Simple single-celled eukaryotes have relatively small amounts of such DNA, whereas the genomes of complex multicellular organisms, including humans, contain an absolute majority of <hl> DNA without an identified function <hl> .


Question: What percentage of the human genome is made of protein coding DNA?

Answer: barely 2%

Whereas the chromosomes of prokaryotes are relatively gene-dense, those of eukaryotes often contain regions of DNA that serve no obvious function. Simple single-celled eukaryotes have relatively small amounts of such DNA, whereas the genomes of complex multicellular organisms, including humans, contain an absolute majority of DNA without an identified function. This DNA has often been referred to as "junk DNA". <hl> However, more recent analyses suggest that, although protein-coding DNA makes up barely 2% of the human genome, about 80% of the bases in the genome may be expressed, so the term "junk DNA" may be a misnomer. <hl>

Whereas the chromosomes of prokaryotes are relatively gene-dense, those of eukaryotes often contain regions of DNA that serve no obvious function. Simple single-celled eukaryotes have relatively small amounts of such DNA, whereas the genomes of complex multicellular organisms, including humans, contain an absolute majority of DNA without an identified function. This DNA has often been referred to as "junk DNA". However, more recent analyses suggest that, although protein-coding DNA makes up <hl> barely 2% <hl> of the human genome, about 80% of the bases in the genome may be expressed, so the term "junk DNA" may be a misnomer.


Question: What percentage of bases in the human genome are expressed by protein coding DNA

Answer: about 80%

Whereas the chromosomes of prokaryotes are relatively gene-dense, those of eukaryotes often contain regions of DNA that serve no obvious function. Simple single-celled eukaryotes have relatively small amounts of such DNA, whereas the genomes of complex multicellular organisms, including humans, contain an absolute majority of DNA without an identified function. This DNA has often been referred to as "junk DNA". <hl> However, more recent analyses suggest that, although protein-coding DNA makes up barely 2% of the human genome, about 80% of the bases in the genome may be expressed, so the term "junk DNA" may be a misnomer. <hl>

Whereas the chromosomes of prokaryotes are relatively gene-dense, those of eukaryotes often contain regions of DNA that serve no obvious function. Simple single-celled eukaryotes have relatively small amounts of such DNA, whereas the genomes of complex multicellular organisms, including humans, contain an absolute majority of DNA without an identified function. This DNA has often been referred to as "junk DNA". However, more recent analyses suggest that, although protein-coding DNA makes up barely 2% of the human genome, <hl> about 80% <hl> of the bases in the genome may be expressed, so the term "junk DNA" may be a misnomer.


Question: Often, how large a part of the structure of a gene is the protein coding sequence?

The structure of a gene consists of many elements of which the actual protein coding sequence is often only a small part. These include DNA regions that are not transcribed as well as untranslated regions of the RNA.

Answer: often only a small part

<hl> The structure of a gene consists of many elements of which the actual protein coding sequence is often only a small part . <hl> These include DNA regions that are not transcribed as well as untranslated regions of the RNA.

The structure of a gene consists of many elements of which the actual protein coding sequence is <hl> often only a small part <hl>. These include DNA regions that are not transcribed as well as untranslated regions of the RNA.

The structure of a gene consists of many elements of which the actual protein coding sequence is <hl> often only a small part <hl> .


Question: What often plays only a small part in the structure of a gene?

Answer: the actual protein coding sequence

<hl> The structure of a gene consists of many elements of which the actual protein coding sequence is often only a small part. <hl> These include DNA regions that are not transcribed as well as untranslated regions of the RNA.

The structure of a gene consists of many elements of which <hl> the actual protein coding sequence <hl> is often only a small part. These include DNA regions that are not transcribed as well as untranslated regions of the RNA.


Question: What is one of the many elements that the structure of a gene consists of?

Answer: DNA regions that are not transcribed

The structure of a gene consists of many elements of which the actual protein coding sequence is often only a small part. <hl> These include DNA regions that are not transcribed as well as untranslated regions of the RNA. <hl>

The structure of a gene consists of many elements of which the actual protein coding sequence is often only a small part. These include <hl> DNA regions that are not transcribed <hl> as well as untranslated regions of the RNA.


Question: What is another element of the structure of a gene?

Answer: untranslated regions of the RNA

The structure of a gene consists of many elements of which the actual protein coding sequence is often only a small part. <hl> These include DNA regions that are not transcribed as well as untranslated regions of the RNA . <hl>

The structure of a gene consists of many elements of which the actual protein coding sequence is often only a small part. These include DNA regions that are not transcribed as well as <hl> untranslated regions of the RNA <hl>.

These include DNA regions that are not transcribed as well as <hl> untranslated regions of the RNA <hl> .


Question: What elements does the structure of a gene consist of?

Answer: DNA regions that are not transcribed as well as untranslated regions of the RNA

The structure of a gene consists of many elements of which the actual protein coding sequence is often only a small part. <hl> These include DNA regions that are not transcribed as well as untranslated regions of the RNA . <hl>

The structure of a gene consists of many elements of which the actual protein coding sequence is often only a small part. These include <hl> DNA regions that are not transcribed as well as untranslated regions of the RNA <hl>.

These include <hl> DNA regions that are not transcribed as well as untranslated regions of the RNA <hl> .


Question: What do all genes contain that is required for their expression?

Firstly, flanking the open reading frame, all genes contain a regulatory sequence that is required for their expression. In order to be expressed, genes require a promoter sequence. The promoter is recognized and bound by transcription factors and RNA polymerase to initiate transcription.:7.1 A gene can have more than one promoter, resulting in messenger RNAs (mRNA) that differ in how far they extend in the 5' end. Promoter regions have a consensus sequence, however highly transcribed genes have "strong" promoter sequences that bind the transcription machinery well, whereas others have "weak" promoters that bind poorly and initiate transcription less frequently.:7.2 Eukaryotic promoter regions are much more complex and difficult to identify than prokaryotic promoters.:7.3

Answer: a regulatory sequence

<hl> Firstly, flanking the open reading frame, all genes contain a regulatory sequence that is required for their expression. <hl> In order to be expressed, genes require a promoter sequence. The promoter is recognized and bound by transcription factors and RNA polymerase to initiate transcription.:7.1 A gene can have more than one promoter, resulting in messenger RNAs (mRNA) that differ in how far they extend in the 5' end. Promoter regions have a consensus sequence, however highly transcribed genes have "strong" promoter sequences that bind the transcription machinery well, whereas others have "weak" promoters that bind poorly and initiate transcription less frequently.:7.2 Eukaryotic promoter regions are much more complex and difficult to identify than prokaryotic promoters.:7.3

Firstly, flanking the open reading frame, all genes contain <hl> a regulatory sequence <hl> that is required for their expression. In order to be expressed, genes require a promoter sequence. The promoter is recognized and bound by transcription factors and RNA polymerase to initiate transcription.:7.1 A gene can have more than one promoter, resulting in messenger RNAs (mRNA) that differ in how far they extend in the 5' end. Promoter regions have a consensus sequence, however highly transcribed genes have "strong" promoter sequences that bind the transcription machinery well, whereas others have "weak" promoters that bind poorly and initiate transcription less frequently.:7.2 Eukaryotic promoter regions are much more complex and difficult to identify than prokaryotic promoters.:7.3


Question: How is a promoter sequence recognized?

Answer: by transcription factors and RNA polymerase

Firstly, flanking the open reading frame, all genes contain a regulatory sequence that is required for their expression. In order to be expressed, genes require a promoter sequence. <hl> The promoter is recognized and bound by transcription factors and RNA polymerase to initiate transcription.:7.1 <hl> A gene can have more than one promoter, resulting in messenger RNAs (mRNA) that differ in how far they extend in the 5' end. Promoter regions have a consensus sequence, however highly transcribed genes have "strong" promoter sequences that bind the transcription machinery well, whereas others have "weak" promoters that bind poorly and initiate transcription less frequently.:7.2 Eukaryotic promoter regions are much more complex and difficult to identify than prokaryotic promoters.:7.3

Firstly, flanking the open reading frame, all genes contain a regulatory sequence that is required for their expression. In order to be expressed, genes require a promoter sequence. The promoter is recognized and bound <hl> by transcription factors and RNA polymerase <hl> to initiate transcription.:7.1 A gene can have more than one promoter, resulting in messenger RNAs (mRNA) that differ in how far they extend in the 5' end. Promoter regions have a consensus sequence, however highly transcribed genes have "strong" promoter sequences that bind the transcription machinery well, whereas others have "weak" promoters that bind poorly and initiate transcription less frequently.:7.2 Eukaryotic promoter regions are much more complex and difficult to identify than prokaryotic promoters.:7.3


Question: What results when genes have more than one promoter?

Answer: messenger RNAs (mRNA) that differ in how far they extend in the 5' end

Firstly, flanking the open reading frame, all genes contain a regulatory sequence that is required for their expression. In order to be expressed, genes require a promoter sequence. The promoter is recognized and bound by transcription factors and RNA polymerase to initiate transcription.:7.1 <hl> A gene can have more than one promoter, resulting in messenger RNAs (mRNA) that differ in how far they extend in the 5' end . <hl> Promoter regions have a consensus sequence, however highly transcribed genes have "strong" promoter sequences that bind the transcription machinery well, whereas others have "weak" promoters that bind poorly and initiate transcription less frequently.:7.2 Eukaryotic promoter regions are much more complex and difficult to identify than prokaryotic promoters.:7.3

Firstly, flanking the open reading frame, all genes contain a regulatory sequence that is required for their expression. In order to be expressed, genes require a promoter sequence. The promoter is recognized and bound by transcription factors and RNA polymerase to initiate transcription.:7.1 A gene can have more than one promoter, resulting in <hl> messenger RNAs (mRNA) that differ in how far they extend in the 5' end <hl>. Promoter regions have a consensus sequence, however highly transcribed genes have "strong" promoter sequences that bind the transcription machinery well, whereas others have "weak" promoters that bind poorly and initiate transcription less frequently.:7.2 Eukaryotic promoter regions are much more complex and difficult to identify than prokaryotic promoters.:7.3

A gene can have more than one promoter, resulting in <hl> messenger RNAs (mRNA) that differ in how far they extend in the 5' end <hl> .


Question: What does a "strong" promoter sequence do?

Answer: bind the transcription machinery well

Firstly, flanking the open reading frame, all genes contain a regulatory sequence that is required for their expression. In order to be expressed, genes require a promoter sequence. The promoter is recognized and bound by transcription factors and RNA polymerase to initiate transcription.:7.1 A gene can have more than one promoter, resulting in messenger RNAs (mRNA) that differ in how far they extend in the 5' end. <hl> Promoter regions have a consensus sequence, however highly transcribed genes have "strong" promoter sequences that bind the transcription machinery well , whereas others have "weak" promoters that bind poorly and initiate transcription less frequently.:7.2 Eukaryotic promoter regions are much more complex and difficult to identify than prokaryotic promoters.:7.3 <hl>

Firstly, flanking the open reading frame, all genes contain a regulatory sequence that is required for their expression. In order to be expressed, genes require a promoter sequence. The promoter is recognized and bound by transcription factors and RNA polymerase to initiate transcription.:7.1 A gene can have more than one promoter, resulting in messenger RNAs (mRNA) that differ in how far they extend in the 5' end. Promoter regions have a consensus sequence, however highly transcribed genes have "strong" promoter sequences that <hl> bind the transcription machinery well <hl>, whereas others have "weak" promoters that bind poorly and initiate transcription less frequently.:7.2 Eukaryotic promoter regions are much more complex and difficult to identify than prokaryotic promoters.:7.3

Promoter regions have a consensus sequence, however highly transcribed genes have "strong" promoter sequences that <hl> bind the transcription machinery well <hl> , whereas others have "weak" promoters that bind poorly and initiate transcription less frequently.:7.2 Eukaryotic promoter regions are much more complex and difficult to identify than prokaryotic promoters.:7.3


Question: What does a "weak" promoter sequence do?

Answer: bind poorly and initiate transcription less frequently

Firstly, flanking the open reading frame, all genes contain a regulatory sequence that is required for their expression. In order to be expressed, genes require a promoter sequence. The promoter is recognized and bound by transcription factors and RNA polymerase to initiate transcription.:7.1 A gene can have more than one promoter, resulting in messenger RNAs (mRNA) that differ in how far they extend in the 5' end. <hl> Promoter regions have a consensus sequence, however highly transcribed genes have "strong" promoter sequences that bind the transcription machinery well, whereas others have "weak" promoters that bind poorly and initiate transcription less frequently .:7.2 <hl> Eukaryotic promoter regions are much more complex and difficult to identify than prokaryotic promoters.:7.3

Firstly, flanking the open reading frame, all genes contain a regulatory sequence that is required for their expression. In order to be expressed, genes require a promoter sequence. The promoter is recognized and bound by transcription factors and RNA polymerase to initiate transcription.:7.1 A gene can have more than one promoter, resulting in messenger RNAs (mRNA) that differ in how far they extend in the 5' end. Promoter regions have a consensus sequence, however highly transcribed genes have "strong" promoter sequences that bind the transcription machinery well, whereas others have "weak" promoters that <hl> bind poorly and initiate transcription less frequently <hl>.:7.2 Eukaryotic promoter regions are much more complex and difficult to identify than prokaryotic promoters.:7.3

Promoter regions have a consensus sequence, however highly transcribed genes have "strong" promoter sequences that bind the transcription machinery well, whereas others have "weak" promoters that <hl> bind poorly and initiate transcription less frequently <hl> .:7.2


Question: How do regulatory regions act?

Additionally, genes can have regulatory regions many kilobases upstream or downstream of the open reading frame. These act by binding to transcription factors which then cause the DNA to loop so that the regulatory sequence (and bound transcription factor) become close to the RNA polymerase binding site. For example, enhancers increase transcription by binding an activator protein which then helps to recruit the RNA polymerase to the promoter; conversely silencers bind repressor proteins and make the DNA less available for RNA polymerase.

Answer: by binding to transcription factors

Additionally, genes can have regulatory regions many kilobases upstream or downstream of the open reading frame. <hl> These act by binding to transcription factors which then cause the DNA to loop so that the regulatory sequence (and bound transcription factor) become close to the RNA polymerase binding site. <hl> For example, enhancers increase transcription by binding an activator protein which then helps to recruit the RNA polymerase to the promoter; conversely silencers bind repressor proteins and make the DNA less available for RNA polymerase.

Additionally, genes can have regulatory regions many kilobases upstream or downstream of the open reading frame. These act <hl> by binding to transcription factors <hl> which then cause the DNA to loop so that the regulatory sequence (and bound transcription factor) become close to the RNA polymerase binding site. For example, enhancers increase transcription by binding an activator protein which then helps to recruit the RNA polymerase to the promoter; conversely silencers bind repressor proteins and make the DNA less available for RNA polymerase.


Question: What happens when a regulatory region binds to transcription factors?

Answer: the DNA to loop

Additionally, genes can have regulatory regions many kilobases upstream or downstream of the open reading frame. <hl> These act by binding to transcription factors which then cause the DNA to loop so that the regulatory sequence (and bound transcription factor) become close to the RNA polymerase binding site. <hl> For example, enhancers increase transcription by binding an activator protein which then helps to recruit the RNA polymerase to the promoter; conversely silencers bind repressor proteins and make the DNA less available for RNA polymerase.

Additionally, genes can have regulatory regions many kilobases upstream or downstream of the open reading frame. These act by binding to transcription factors which then cause <hl> the DNA to loop <hl> so that the regulatory sequence (and bound transcription factor) become close to the RNA polymerase binding site. For example, enhancers increase transcription by binding an activator protein which then helps to recruit the RNA polymerase to the promoter; conversely silencers bind repressor proteins and make the DNA less available for RNA polymerase.


Question: How do enhancers increase transcription?

Answer: by binding an activator protein

Additionally, genes can have regulatory regions many kilobases upstream or downstream of the open reading frame. These act by binding to transcription factors which then cause the DNA to loop so that the regulatory sequence (and bound transcription factor) become close to the RNA polymerase binding site. <hl> For example, enhancers increase transcription by binding an activator protein which then helps to recruit the RNA polymerase to the promoter; conversely silencers bind repressor proteins and make the DNA less available for RNA polymerase. <hl>

Additionally, genes can have regulatory regions many kilobases upstream or downstream of the open reading frame. These act by binding to transcription factors which then cause the DNA to loop so that the regulatory sequence (and bound transcription factor) become close to the RNA polymerase binding site. For example, enhancers increase transcription <hl> by binding an activator protein <hl> which then helps to recruit the RNA polymerase to the promoter; conversely silencers bind repressor proteins and make the DNA less available for RNA polymerase.


Question: What happens after an enhancer binds an activator protein?

Answer: helps to recruit the RNA polymerase to the promoter

Additionally, genes can have regulatory regions many kilobases upstream or downstream of the open reading frame. These act by binding to transcription factors which then cause the DNA to loop so that the regulatory sequence (and bound transcription factor) become close to the RNA polymerase binding site. <hl> For example, enhancers increase transcription by binding an activator protein which then helps to recruit the RNA polymerase to the promoter ; conversely silencers bind repressor proteins and make the DNA less available for RNA polymerase. <hl>

Additionally, genes can have regulatory regions many kilobases upstream or downstream of the open reading frame. These act by binding to transcription factors which then cause the DNA to loop so that the regulatory sequence (and bound transcription factor) become close to the RNA polymerase binding site. For example, enhancers increase transcription by binding an activator protein which then <hl> helps to recruit the RNA polymerase to the promoter <hl>; conversely silencers bind repressor proteins and make the DNA less available for RNA polymerase.

For example, enhancers increase transcription by binding an activator protein which then <hl> helps to recruit the RNA polymerase to the promoter <hl> ; conversely silencers bind repressor proteins and make the DNA less available for RNA polymerase.


Question: What causes DNA to be less available for RNA polymerase?

Answer: silencers bind repressor proteins

Additionally, genes can have regulatory regions many kilobases upstream or downstream of the open reading frame. These act by binding to transcription factors which then cause the DNA to loop so that the regulatory sequence (and bound transcription factor) become close to the RNA polymerase binding site. <hl> For example, enhancers increase transcription by binding an activator protein which then helps to recruit the RNA polymerase to the promoter; conversely silencers bind repressor proteins and make the DNA less available for RNA polymerase. <hl>

Additionally, genes can have regulatory regions many kilobases upstream or downstream of the open reading frame. These act by binding to transcription factors which then cause the DNA to loop so that the regulatory sequence (and bound transcription factor) become close to the RNA polymerase binding site. For example, enhancers increase transcription by binding an activator protein which then helps to recruit the RNA polymerase to the promoter; conversely <hl> silencers bind repressor proteins <hl> and make the DNA less available for RNA polymerase.


Question: What is at both ends of the transcribed pre-mRNA?

The transcribed pre-mRNA contains untranslated regions at both ends which contain a ribosome binding site, terminator and start and stop codons. In addition, most eukaryotic open reading frames contain untranslated introns which are removed before the exons are translated. The sequences at the ends of the introns, dictate the splice sites to generate the final mature mRNA which encodes the protein or RNA product.

Answer: untranslated regions

<hl> The transcribed pre-mRNA contains untranslated regions at both ends which contain a ribosome binding site, terminator and start and stop codons. <hl> In addition, most eukaryotic open reading frames contain untranslated introns which are removed before the exons are translated. The sequences at the ends of the introns, dictate the splice sites to generate the final mature mRNA which encodes the protein or RNA product.

The transcribed pre-mRNA contains <hl> untranslated regions <hl> at both ends which contain a ribosome binding site, terminator and start and stop codons. In addition, most eukaryotic open reading frames contain untranslated introns which are removed before the exons are translated. The sequences at the ends of the introns, dictate the splice sites to generate the final mature mRNA which encodes the protein or RNA product.


Question: Where are the ribosome binding site, terminator and start and stop codons located on transcribed pre-mRNA?

Answer: untranslated regions

<hl> The transcribed pre-mRNA contains untranslated regions at both ends which contain a ribosome binding site, terminator and start and stop codons. <hl> In addition, most eukaryotic open reading frames contain untranslated introns which are removed before the exons are translated. The sequences at the ends of the introns, dictate the splice sites to generate the final mature mRNA which encodes the protein or RNA product.

The transcribed pre-mRNA contains <hl> untranslated regions <hl> at both ends which contain a ribosome binding site, terminator and start and stop codons. In addition, most eukaryotic open reading frames contain untranslated introns which are removed before the exons are translated. The sequences at the ends of the introns, dictate the splice sites to generate the final mature mRNA which encodes the protein or RNA product.


Question: What do most eukaryotic open reading frames contain?

Answer: untranslated introns

The transcribed pre-mRNA contains untranslated regions at both ends which contain a ribosome binding site, terminator and start and stop codons. <hl> In addition, most eukaryotic open reading frames contain untranslated introns which are removed before the exons are translated. <hl> The sequences at the ends of the introns, dictate the splice sites to generate the final mature mRNA which encodes the protein or RNA product.

The transcribed pre-mRNA contains untranslated regions at both ends which contain a ribosome binding site, terminator and start and stop codons. In addition, most eukaryotic open reading frames contain <hl> untranslated introns <hl> which are removed before the exons are translated. The sequences at the ends of the introns, dictate the splice sites to generate the final mature mRNA which encodes the protein or RNA product.


Question: What dictates the splice sites to generate the final mature mRNA?

Answer: The sequences at the ends of the introns

The transcribed pre-mRNA contains untranslated regions at both ends which contain a ribosome binding site, terminator and start and stop codons. In addition, most eukaryotic open reading frames contain untranslated introns which are removed before the exons are translated. <hl> The sequences at the ends of the introns , dictate the splice sites to generate the final mature mRNA which encodes the protein or RNA product. <hl>

The transcribed pre-mRNA contains untranslated regions at both ends which contain a ribosome binding site, terminator and start and stop codons. In addition, most eukaryotic open reading frames contain untranslated introns which are removed before the exons are translated. <hl> The sequences at the ends of the introns <hl>, dictate the splice sites to generate the final mature mRNA which encodes the protein or RNA product.

<hl> The sequences at the ends of the introns <hl> , dictate the splice sites to generate the final mature mRNA which encodes the protein or RNA product.


Question: What encodes the protein or RNA product?

Answer: the splice sites to generate the final mature mRNA

The transcribed pre-mRNA contains untranslated regions at both ends which contain a ribosome binding site, terminator and start and stop codons. In addition, most eukaryotic open reading frames contain untranslated introns which are removed before the exons are translated. <hl> The sequences at the ends of the introns, dictate the splice sites to generate the final mature mRNA which encodes the protein or RNA product. <hl>

The transcribed pre-mRNA contains untranslated regions at both ends which contain a ribosome binding site, terminator and start and stop codons. In addition, most eukaryotic open reading frames contain untranslated introns which are removed before the exons are translated. The sequences at the ends of the introns, dictate <hl> the splice sites to generate the final mature mRNA <hl> which encodes the protein or RNA product.


Question: What are most prokaryotic genes organized into?

Many prokaryotic genes are organized into operons, with multiple protein-coding sequences that are transcribed as a unit. The products of operon genes typically have related functions and are involved in the same regulatory network.:7.3

Answer: operons

<hl> Many prokaryotic genes are organized into operons , with multiple protein-coding sequences that are transcribed as a unit. <hl> The products of operon genes typically have related functions and are involved in the same regulatory network.:7.3

Many prokaryotic genes are organized into <hl> operons <hl>, with multiple protein-coding sequences that are transcribed as a unit. The products of operon genes typically have related functions and are involved in the same regulatory network.:7.3

Many prokaryotic genes are organized into <hl> operons <hl> , with multiple protein-coding sequences that are transcribed as a unit.


Question: What are multiple protein coding sequences transcribed as?

Answer: a unit

<hl> Many prokaryotic genes are organized into operons, with multiple protein-coding sequences that are transcribed as a unit . <hl> The products of operon genes typically have related functions and are involved in the same regulatory network.:7.3

Many prokaryotic genes are organized into operons, with multiple protein-coding sequences that are transcribed as <hl> a unit <hl>. The products of operon genes typically have related functions and are involved in the same regulatory network.:7.3

Many prokaryotic genes are organized into operons, with multiple protein-coding sequences that are transcribed as <hl> a unit <hl> .


Question: What sort of functions do the products of operon genes typically have?

Answer: related functions

Many prokaryotic genes are organized into operons, with multiple protein-coding sequences that are transcribed as a unit. <hl> The products of operon genes typically have related functions and are involved in the same regulatory network.:7.3 <hl>

Many prokaryotic genes are organized into operons, with multiple protein-coding sequences that are transcribed as a unit. The products of operon genes typically have <hl> related functions <hl> and are involved in the same regulatory network.:7.3


Question: What type of network are the products of operon genes typically involved with?

Answer: the same regulatory network

Many prokaryotic genes are organized into operons, with multiple protein-coding sequences that are transcribed as a unit. <hl> The products of operon genes typically have related functions and are involved in the same regulatory network .:7.3 <hl>

Many prokaryotic genes are organized into operons, with multiple protein-coding sequences that are transcribed as a unit. The products of operon genes typically have related functions and are involved in <hl> the same regulatory network <hl>.:7.3

The products of operon genes typically have related functions and are involved in <hl> the same regulatory network <hl> .:7.3


Question: What type of coding sequences do prokaryotic genes typically have?

Answer: multiple protein-coding sequences

<hl> Many prokaryotic genes are organized into operons, with multiple protein-coding sequences that are transcribed as a unit. <hl> The products of operon genes typically have related functions and are involved in the same regulatory network.:7.3

Many prokaryotic genes are organized into operons, with <hl> multiple protein-coding sequences <hl> that are transcribed as a unit. The products of operon genes typically have related functions and are involved in the same regulatory network.:7.3


Question: What is an example of a regulatory region of a gene that does not have to close to the coding sequence?

Defining exactly what section of a DNA sequence comprises a gene is difficult. Regulatory regions of a gene such as enhancers do not necessarily have to be close to the coding sequence on the linear molecule because the intervening DNA can be looped out to bring the gene and its regulatory region into proximity. Similarly, a gene's introns can be much larger than its exons. Regulatory regions can even be on entirely different chromosomes and operate in trans to allow regulatory regions on one chromosome to come in contact with target genes on another chromosome.

Answer: enhancers

Defining exactly what section of a DNA sequence comprises a gene is difficult. <hl> Regulatory regions of a gene such as enhancers do not necessarily have to be close to the coding sequence on the linear molecule because the intervening DNA can be looped out to bring the gene and its regulatory region into proximity. <hl> Similarly, a gene's introns can be much larger than its exons. Regulatory regions can even be on entirely different chromosomes and operate in trans to allow regulatory regions on one chromosome to come in contact with target genes on another chromosome.

Defining exactly what section of a DNA sequence comprises a gene is difficult. Regulatory regions of a gene such as <hl> enhancers <hl> do not necessarily have to be close to the coding sequence on the linear molecule because the intervening DNA can be looped out to bring the gene and its regulatory region into proximity. Similarly, a gene's introns can be much larger than its exons. Regulatory regions can even be on entirely different chromosomes and operate in trans to allow regulatory regions on one chromosome to come in contact with target genes on another chromosome.


Question: Why do some regulatory regions of a gene not have to be close to the coding sequence?

Answer: because the intervening DNA can be looped out to bring the gene and its regulatory region into proximity

Defining exactly what section of a DNA sequence comprises a gene is difficult. <hl> Regulatory regions of a gene such as enhancers do not necessarily have to be close to the coding sequence on the linear molecule because the intervening DNA can be looped out to bring the gene and its regulatory region into proximity . <hl> Similarly, a gene's introns can be much larger than its exons. Regulatory regions can even be on entirely different chromosomes and operate in trans to allow regulatory regions on one chromosome to come in contact with target genes on another chromosome.

Defining exactly what section of a DNA sequence comprises a gene is difficult. Regulatory regions of a gene such as enhancers do not necessarily have to be close to the coding sequence on the linear molecule <hl> because the intervening DNA can be looped out to bring the gene and its regulatory region into proximity <hl>. Similarly, a gene's introns can be much larger than its exons. Regulatory regions can even be on entirely different chromosomes and operate in trans to allow regulatory regions on one chromosome to come in contact with target genes on another chromosome.

Regulatory regions of a gene such as enhancers do not necessarily have to be close to the coding sequence on the linear molecule <hl> because the intervening DNA can be looped out to bring the gene and its regulatory region into proximity <hl> .


Question: What part of a gene can be much larger than its exons?

Answer: a gene's introns

Defining exactly what section of a DNA sequence comprises a gene is difficult. Regulatory regions of a gene such as enhancers do not necessarily have to be close to the coding sequence on the linear molecule because the intervening DNA can be looped out to bring the gene and its regulatory region into proximity. <hl> Similarly, a gene's introns can be much larger than its exons. <hl> Regulatory regions can even be on entirely different chromosomes and operate in trans to allow regulatory regions on one chromosome to come in contact with target genes on another chromosome.

Defining exactly what section of a DNA sequence comprises a gene is difficult. Regulatory regions of a gene such as enhancers do not necessarily have to be close to the coding sequence on the linear molecule because the intervening DNA can be looped out to bring the gene and its regulatory region into proximity. Similarly, <hl> a gene's introns <hl> can be much larger than its exons. Regulatory regions can even be on entirely different chromosomes and operate in trans to allow regulatory regions on one chromosome to come in contact with target genes on another chromosome.


Question: How do regulatory regions on different chromosomes operate in order to allow regions on different chromosomes to come into contact with one another?

Answer: in trans

Defining exactly what section of a DNA sequence comprises a gene is difficult. Regulatory regions of a gene such as enhancers do not necessarily have to be close to the coding sequence on the linear molecule because the intervening DNA can be looped out to bring the gene and its regulatory region into proximity. Similarly, a gene's introns can be much larger than its exons. <hl> Regulatory regions can even be on entirely different chromosomes and operate in trans to allow regulatory regions on one chromosome to come in contact with target genes on another chromosome. <hl>

Defining exactly what section of a DNA sequence comprises a gene is difficult. Regulatory regions of a gene such as enhancers do not necessarily have to be close to the coding sequence on the linear molecule because the intervening DNA can be looped out to bring the gene and its regulatory region into proximity. Similarly, a gene's introns can be much larger than its exons. Regulatory regions can even be on entirely different chromosomes and operate <hl> in trans <hl> to allow regulatory regions on one chromosome to come in contact with target genes on another chromosome.


Question: Where can regulatory regions be found?

Answer: different chromosomes

Defining exactly what section of a DNA sequence comprises a gene is difficult. Regulatory regions of a gene such as enhancers do not necessarily have to be close to the coding sequence on the linear molecule because the intervening DNA can be looped out to bring the gene and its regulatory region into proximity. Similarly, a gene's introns can be much larger than its exons. <hl> Regulatory regions can even be on entirely different chromosomes and operate in trans to allow regulatory regions on one chromosome to come in contact with target genes on another chromosome. <hl>

Defining exactly what section of a DNA sequence comprises a gene is difficult. Regulatory regions of a gene such as enhancers do not necessarily have to be close to the coding sequence on the linear molecule because the intervening DNA can be looped out to bring the gene and its regulatory region into proximity. Similarly, a gene's introns can be much larger than its exons. Regulatory regions can even be on entirely <hl> different chromosomes <hl> and operate in trans to allow regulatory regions on one chromosome to come in contact with target genes on another chromosome.


Question: What model did early work in molecular genetics suggest?

Answer: the model that one gene makes one protein.

<hl> Early work in molecular genetics suggested the model that one gene makes one protein. This model has been refined since the discovery of genes that can encode multiple proteins by alternative splicing and coding sequences split in short section across the genome whose mRNAs are concatenated by trans-splicing. <hl>

Early work in molecular genetics suggested <hl> the model that one gene makes one protein. <hl> This model has been refined since the discovery of genes that can encode multiple proteins by alternative splicing and coding sequences split in short section across the genome whose mRNAs are concatenated by trans-splicing.


Question: What discovery caused the model that one gene makes one protein to be refined?

Answer: the discovery of genes that can encode multiple proteins

Early work in molecular genetics suggested the model that one gene makes one protein. <hl> This model has been refined since the discovery of genes that can encode multiple proteins by alternative splicing and coding sequences split in short section across the genome whose mRNAs are concatenated by trans-splicing. <hl>

Early work in molecular genetics suggested the model that one gene makes one protein. This model has been refined since <hl> the discovery of genes that can encode multiple proteins <hl> by alternative splicing and coding sequences split in short section across the genome whose mRNAs are concatenated by trans-splicing.


Question: How do genes encode multiple proteins?

Answer: by alternative splicing and coding sequences

Early work in molecular genetics suggested the model that one gene makes one protein. <hl> This model has been refined since the discovery of genes that can encode multiple proteins by alternative splicing and coding sequences split in short section across the genome whose mRNAs are concatenated by trans-splicing. <hl>

Early work in molecular genetics suggested the model that one gene makes one protein. This model has been refined since the discovery of genes that can encode multiple proteins <hl> by alternative splicing and coding sequences <hl> split in short section across the genome whose mRNAs are concatenated by trans-splicing.


Question: How are alternative splicing and coding sequences distributed?

Answer: split in short section across the genome

Early work in molecular genetics suggested the model that one gene makes one protein. <hl> This model has been refined since the discovery of genes that can encode multiple proteins by alternative splicing and coding sequences split in short section across the genome whose mRNAs are concatenated by trans-splicing. <hl>

Early work in molecular genetics suggested the model that one gene makes one protein. This model has been refined since the discovery of genes that can encode multiple proteins by alternative splicing and coding sequences <hl> split in short section across the genome <hl> whose mRNAs are concatenated by trans-splicing.


Question: In order for a gene to encode multiple proteins, how must its mRNAs be arranged?

Answer: concatenated by trans-splicing.

Early work in molecular genetics suggested the model that one gene makes one protein. <hl> This model has been refined since the discovery of genes that can encode multiple proteins by alternative splicing and coding sequences split in short section across the genome whose mRNAs are concatenated by trans-splicing. <hl>

Early work in molecular genetics suggested the model that one gene makes one protein. This model has been refined since the discovery of genes that can encode multiple proteins by alternative splicing and coding sequences split in short section across the genome whose mRNAs are <hl> concatenated by trans-splicing. <hl>


Question: What sort of definition can be used to conveniently encompass the complexity of diverse phenomena?

A broad operational definition is sometimes used to encompass the complexity of these diverse phenomena, where a gene is defined as a union of genomic sequences encoding a coherent set of potentially overlapping functional products. This definition categorizes genes by their functional products (proteins or RNA) rather than their specific DNA loci, with regulatory elements classified as gene-associated regions.

Answer: A broad operational definition

<hl> A broad operational definition is sometimes used to encompass the complexity of these diverse phenomena, where a gene is defined as a union of genomic sequences encoding a coherent set of potentially overlapping functional products. <hl> This definition categorizes genes by their functional products (proteins or RNA) rather than their specific DNA loci, with regulatory elements classified as gene-associated regions.

<hl> A broad operational definition <hl> is sometimes used to encompass the complexity of these diverse phenomena, where a gene is defined as a union of genomic sequences encoding a coherent set of potentially overlapping functional products. This definition categorizes genes by their functional products (proteins or RNA) rather than their specific DNA loci, with regulatory elements classified as gene-associated regions.


Question: What is the broad operational definition of a gene?

Answer: a union of genomic sequences encoding a coherent set of potentially overlapping functional products

<hl> A broad operational definition is sometimes used to encompass the complexity of these diverse phenomena, where a gene is defined as a union of genomic sequences encoding a coherent set of potentially overlapping functional products . <hl> This definition categorizes genes by their functional products (proteins or RNA) rather than their specific DNA loci, with regulatory elements classified as gene-associated regions.

A broad operational definition is sometimes used to encompass the complexity of these diverse phenomena, where a gene is defined as <hl> a union of genomic sequences encoding a coherent set of potentially overlapping functional products <hl>. This definition categorizes genes by their functional products (proteins or RNA) rather than their specific DNA loci, with regulatory elements classified as gene-associated regions.

A broad operational definition is sometimes used to encompass the complexity of these diverse phenomena, where a gene is defined as <hl> a union of genomic sequences encoding a coherent set of potentially overlapping functional products <hl> .


Question: What does the typical definition of a gene categorize genes by?

Answer: their specific DNA loci

A broad operational definition is sometimes used to encompass the complexity of these diverse phenomena, where a gene is defined as a union of genomic sequences encoding a coherent set of potentially overlapping functional products. <hl> This definition categorizes genes by their functional products (proteins or RNA) rather than their specific DNA loci , with regulatory elements classified as gene-associated regions. <hl>

A broad operational definition is sometimes used to encompass the complexity of these diverse phenomena, where a gene is defined as a union of genomic sequences encoding a coherent set of potentially overlapping functional products. This definition categorizes genes by their functional products (proteins or RNA) rather than <hl> their specific DNA loci <hl>, with regulatory elements classified as gene-associated regions.

This definition categorizes genes by their functional products (proteins or RNA) rather than <hl> their specific DNA loci <hl> , with regulatory elements classified as gene-associated regions.


Question: What does the broad operational definition of gene categorize genes by?

Answer: their functional products (proteins or RNA)

A broad operational definition is sometimes used to encompass the complexity of these diverse phenomena, where a gene is defined as a union of genomic sequences encoding a coherent set of potentially overlapping functional products. <hl> This definition categorizes genes by their functional products (proteins or RNA) rather than their specific DNA loci, with regulatory elements classified as gene-associated regions. <hl>

A broad operational definition is sometimes used to encompass the complexity of these diverse phenomena, where a gene is defined as a union of genomic sequences encoding a coherent set of potentially overlapping functional products. This definition categorizes genes by <hl> their functional products (proteins or RNA) <hl> rather than their specific DNA loci, with regulatory elements classified as gene-associated regions.


Question: What does the broad operational definition of a gene classify as gene-associated regions?

Answer: regulatory elements

A broad operational definition is sometimes used to encompass the complexity of these diverse phenomena, where a gene is defined as a union of genomic sequences encoding a coherent set of potentially overlapping functional products. <hl> This definition categorizes genes by their functional products (proteins or RNA) rather than their specific DNA loci, with regulatory elements classified as gene-associated regions. <hl>

A broad operational definition is sometimes used to encompass the complexity of these diverse phenomena, where a gene is defined as a union of genomic sequences encoding a coherent set of potentially overlapping functional products. This definition categorizes genes by their functional products (proteins or RNA) rather than their specific DNA loci, with <hl> regulatory elements <hl> classified as gene-associated regions.


Question: How many steps are required to read the information encoded in a gene's DNA and produce the specified protein?

In all organisms, two steps are required to read the information encoded in a gene's DNA and produce the protein it specifies. First, the gene's DNA is transcribed to messenger RNA (mRNA).:6.1 Second, that mRNA is translated to protein.:6.2 RNA-coding genes must still go through the first step, but are not translated into protein. The process of producing a biologically functional molecule of either RNA or protein is called gene expression, and the resulting molecule is called a gene product.

Answer: two steps are required

<hl> In all organisms, two steps are required to read the information encoded in a gene's DNA and produce the protein it specifies. <hl> First, the gene's DNA is transcribed to messenger RNA (mRNA).:6.1 Second, that mRNA is translated to protein.:6.2 RNA-coding genes must still go through the first step, but are not translated into protein. The process of producing a biologically functional molecule of either RNA or protein is called gene expression, and the resulting molecule is called a gene product.

In all organisms, <hl> two steps are required <hl> to read the information encoded in a gene's DNA and produce the protein it specifies. First, the gene's DNA is transcribed to messenger RNA (mRNA).:6.1 Second, that mRNA is translated to protein.:6.2 RNA-coding genes must still go through the first step, but are not translated into protein. The process of producing a biologically functional molecule of either RNA or protein is called gene expression, and the resulting molecule is called a gene product.


Question: What is the first step to read the information encoded in a gene's DNA and produce the protein it specifies?

Answer: the gene's DNA is transcribed to messenger RNA (mRNA)

In all organisms, two steps are required to read the information encoded in a gene's DNA and produce the protein it specifies. <hl> First, the gene's DNA is transcribed to messenger RNA (mRNA) .:6.1 <hl> Second, that mRNA is translated to protein.:6.2 RNA-coding genes must still go through the first step, but are not translated into protein. The process of producing a biologically functional molecule of either RNA or protein is called gene expression, and the resulting molecule is called a gene product.

In all organisms, two steps are required to read the information encoded in a gene's DNA and produce the protein it specifies. First, <hl> the gene's DNA is transcribed to messenger RNA (mRNA) <hl>.:6.1 Second, that mRNA is translated to protein.:6.2 RNA-coding genes must still go through the first step, but are not translated into protein. The process of producing a biologically functional molecule of either RNA or protein is called gene expression, and the resulting molecule is called a gene product.

First, <hl> the gene's DNA is transcribed to messenger RNA (mRNA) <hl> .:6.1


Question: What is the second step to read the information encoded in a gene's DNA and produce the protein it specifies?

Answer: mRNA is translated to protein

In all organisms, two steps are required to read the information encoded in a gene's DNA and produce the protein it specifies. <hl> First, the gene's DNA is transcribed to messenger RNA (mRNA).:6.1 Second, that mRNA is translated to protein .:6.2 <hl> RNA-coding genes must still go through the first step, but are not translated into protein. The process of producing a biologically functional molecule of either RNA or protein is called gene expression, and the resulting molecule is called a gene product.

In all organisms, two steps are required to read the information encoded in a gene's DNA and produce the protein it specifies. First, the gene's DNA is transcribed to messenger RNA (mRNA).:6.1 Second, that <hl> mRNA is translated to protein <hl>.:6.2 RNA-coding genes must still go through the first step, but are not translated into protein. The process of producing a biologically functional molecule of either RNA or protein is called gene expression, and the resulting molecule is called a gene product.

First, the gene's DNA is transcribed to messenger RNA (mRNA).:6.1 Second, that <hl> mRNA is translated to protein <hl> .:6.2


Question: What step must RNA-coding genes still go through?

Answer: the first step

In all organisms, two steps are required to read the information encoded in a gene's DNA and produce the protein it specifies. <hl> First, the gene's DNA is transcribed to messenger RNA (mRNA).:6.1 Second, that mRNA is translated to protein.:6.2 RNA-coding genes must still go through the first step , but are not translated into protein. <hl> The process of producing a biologically functional molecule of either RNA or protein is called gene expression, and the resulting molecule is called a gene product.

In all organisms, two steps are required to read the information encoded in a gene's DNA and produce the protein it specifies. First, the gene's DNA is transcribed to messenger RNA (mRNA).:6.1 Second, that mRNA is translated to protein.:6.2 RNA-coding genes must still go through <hl> the first step <hl>, but are not translated into protein. The process of producing a biologically functional molecule of either RNA or protein is called gene expression, and the resulting molecule is called a gene product.

First, the gene's DNA is transcribed to messenger RNA (mRNA).:6.1 Second, that mRNA is translated to protein.:6.2 RNA-coding genes must still go through <hl> the first step <hl> , but are not translated into protein.


Question: What is the process of producing a biologically functional molecule of either RNA or protein called?

Answer: gene expression

In all organisms, two steps are required to read the information encoded in a gene's DNA and produce the protein it specifies. First, the gene's DNA is transcribed to messenger RNA (mRNA).:6.1 Second, that mRNA is translated to protein.:6.2 RNA-coding genes must still go through the first step, but are not translated into protein. <hl> The process of producing a biologically functional molecule of either RNA or protein is called gene expression , and the resulting molecule is called a gene product. <hl>

In all organisms, two steps are required to read the information encoded in a gene's DNA and produce the protein it specifies. First, the gene's DNA is transcribed to messenger RNA (mRNA).:6.1 Second, that mRNA is translated to protein.:6.2 RNA-coding genes must still go through the first step, but are not translated into protein. The process of producing a biologically functional molecule of either RNA or protein is called <hl> gene expression <hl>, and the resulting molecule is called a gene product.

The process of producing a biologically functional molecule of either RNA or protein is called <hl> gene expression <hl> , and the resulting molecule is called a gene product.


Question: What specifies the amino acid sequence of a protein?

The nucleotide sequence of a gene's DNA specifies the amino acid sequence of a protein through the genetic code. Sets of three nucleotides, known as codons, each correspond to a specific amino acid.:6 Additionally, a "start codon", and three "stop codons" indicate the beginning and end of the protein coding region. There are 64 possible codons (four possible nucleotides at each of three positions, hence 43 possible codons) and only 20 standard amino acids; hence the code is redundant and multiple codons can specify the same amino acid. The correspondence between codons and amino acids is nearly universal among all known living organisms.

Answer: The nucleotide sequence of a gene's DNA

<hl> The nucleotide sequence of a gene's DNA specifies the amino acid sequence of a protein through the genetic code. <hl> Sets of three nucleotides, known as codons, each correspond to a specific amino acid.:6 Additionally, a "start codon", and three "stop codons" indicate the beginning and end of the protein coding region. There are 64 possible codons (four possible nucleotides at each of three positions, hence 43 possible codons) and only 20 standard amino acids; hence the code is redundant and multiple codons can specify the same amino acid. The correspondence between codons and amino acids is nearly universal among all known living organisms.

<hl> The nucleotide sequence of a gene's DNA <hl> specifies the amino acid sequence of a protein through the genetic code. Sets of three nucleotides, known as codons, each correspond to a specific amino acid.:6 Additionally, a "start codon", and three "stop codons" indicate the beginning and end of the protein coding region. There are 64 possible codons (four possible nucleotides at each of three positions, hence 43 possible codons) and only 20 standard amino acids; hence the code is redundant and multiple codons can specify the same amino acid. The correspondence between codons and amino acids is nearly universal among all known living organisms.


Question: What are sets of three nucleotides known as?

Answer: codons

The nucleotide sequence of a gene's DNA specifies the amino acid sequence of a protein through the genetic code. <hl> Sets of three nucleotides, known as codons , each correspond to a specific amino acid.:6 Additionally, a "start codon", and three "stop codons" indicate the beginning and end of the protein coding region. <hl> There are 64 possible codons (four possible nucleotides at each of three positions, hence 43 possible codons) and only 20 standard amino acids; hence the code is redundant and multiple codons can specify the same amino acid. The correspondence between codons and amino acids is nearly universal among all known living organisms.

The nucleotide sequence of a gene's DNA specifies the amino acid sequence of a protein through the genetic code. Sets of three nucleotides, known as <hl> codons <hl>, each correspond to a specific amino acid.:6 Additionally, a "start codon", and three "stop codons" indicate the beginning and end of the protein coding region. There are 64 possible codons (four possible nucleotides at each of three positions, hence 43 possible codons) and only 20 standard amino acids; hence the code is redundant and multiple codons can specify the same amino acid. The correspondence between codons and amino acids is nearly universal among all known living organisms.

Sets of three nucleotides, known as <hl> codons <hl> , each correspond to a specific amino acid.:6 Additionally, a "start codon", and three "stop codons" indicate the beginning and end of the protein coding region.


Question: What does each codon correspond to?

Answer: a specific amino acid

The nucleotide sequence of a gene's DNA specifies the amino acid sequence of a protein through the genetic code. <hl> Sets of three nucleotides, known as codons, each correspond to a specific amino acid .:6 <hl> Additionally, a "start codon", and three "stop codons" indicate the beginning and end of the protein coding region. There are 64 possible codons (four possible nucleotides at each of three positions, hence 43 possible codons) and only 20 standard amino acids; hence the code is redundant and multiple codons can specify the same amino acid. The correspondence between codons and amino acids is nearly universal among all known living organisms.

The nucleotide sequence of a gene's DNA specifies the amino acid sequence of a protein through the genetic code. Sets of three nucleotides, known as codons, each correspond to <hl> a specific amino acid <hl>.:6 Additionally, a "start codon", and three "stop codons" indicate the beginning and end of the protein coding region. There are 64 possible codons (four possible nucleotides at each of three positions, hence 43 possible codons) and only 20 standard amino acids; hence the code is redundant and multiple codons can specify the same amino acid. The correspondence between codons and amino acids is nearly universal among all known living organisms.

Sets of three nucleotides, known as codons, each correspond to <hl> a specific amino acid <hl> .:6