In fundamental genetics, what best describes an organism's genotype?

• A. A population's overall allele frequencies
• B. The observable traits expressed by an organism
• C. The specific alleles an organism carries for a gene or set of genes
• D. The physical location of a gene on a chromosome

Answer: (C)

Verified step by step guidance

1. Understand that genotype refers to the genetic makeup of an organism, specifically the alleles it carries for a particular gene or set of genes.
2. Differentiate genotype from phenotype, where phenotype is the observable traits or characteristics expressed by the organism.
3. Recognize that allele frequencies describe a population-level concept, not an individual organism's genotype.
4. Note that the physical location of a gene on a chromosome is called the gene's locus, which is different from genotype.
5. Conclude that the best description of an organism's genotype is the specific alleles it carries for a gene or set of genes.