Final answer:
A gene is a unit of heredity and codes for proteins or functional RNA molecules, containing DNA which is transcribed into RNA that is then translated to produce proteins.
Step-by-step explanation:
Among the statements provided, the ones that correctly describe a gene are:
- A gene is a unit of heredity.
- A gene codes for a protein or functional RNA molecule.
A gene is composed of DNA and is the fundamental physical and functional unit of heredity. Genes are linearly arranged on chromosomes and are responsible for determining the sequence of amino acids in proteins. The process begins with transcription, in which a segment of DNA is 'read' to produce an RNA molecule. For most genes, this RNA molecule is messenger RNA (mRNA), which then undergoes translation to synthesize a specific protein based on the sequence encoded by the gene. This sequence of events—from DNA to RNA to protein—reflects the central dogma of molecular biology.