Which statement about genes is accurate?

Which statement about genes is accurate?

• A. Genes are continuous spans of amino acids.
• B. Genes are copies of enzymes.
• C. Genes are unconnected segments of the genome.
• D. Genes are discrete units of heredity information consisting of a specific nucleotide sequence.

Answer: (D)

Genes are discrete units of heredity information carried by a specific sequence of nucleotides in the genome. That precise nucleotide sequence holds the instructions to make RNA and, typically, proteins, which then influence inherited traits. This is why the accurate statement describes genes as units of heredity info defined by a particular nucleotide sequence—the information carrier is the DNA sequence, not an amino acid chain or an enzyme itself. The first option isn’t correct because genes are not continuous spans of amino acids; amino acids are the building blocks of the proteins that genes can encode, but the gene itself is defined by its nucleotide code, not by a chain of amino acids. The second option is off because a gene isn’t simply a copy of an enzyme; while some genes code for enzymes, a gene is the hereditary unit, and its product can be an RNA or a protein, not necessarily an enzyme. The third option doesn’t fit perfectly either because genes are defined segments within the genome that carry information; they can be separated by noncoding regions or introns, but the essential idea is that each gene corresponds to a discrete nucleotide sequence that stores hereditary information.

Genes are discrete units of heredity information carried by a specific sequence of nucleotides in the genome. That precise nucleotide sequence holds the instructions to make RNA and, typically, proteins, which then influence inherited traits. This is why the accurate statement describes genes as units of heredity info defined by a particular nucleotide sequence—the information carrier is the DNA sequence, not an amino acid chain or an enzyme itself.

The first option isn’t correct because genes are not continuous spans of amino acids; amino acids are the building blocks of the proteins that genes can encode, but the gene itself is defined by its nucleotide code, not by a chain of amino acids. The second option is off because a gene isn’t simply a copy of an enzyme; while some genes code for enzymes, a gene is the hereditary unit, and its product can be an RNA or a protein, not necessarily an enzyme. The third option doesn’t fit perfectly either because genes are defined segments within the genome that carry information; they can be separated by noncoding regions or introns, but the essential idea is that each gene corresponds to a discrete nucleotide sequence that stores hereditary information.