Biological Anthropology Practice Exam 2026 – Full Study Resource

Genotype describes the genetic makeup of an individual, specifically the alleles present at a given locus on the pair of homologous chromosomes. In diploid organisms, you have two copies of each chromosome, so there are two alleles for each gene. The combination of those alleles constitutes the genotype at that locus and can be homozygous (same allele on both chromosomes, like AA or aa) or heterozygous (two different alleles, like Aa). This is separate from the phenotype, which is what you can observe about the organism and is shaped by both the genotype and the environment. The genome, by contrast, is the entire set of genetic material in an organism, across all loci, not just a single locus. Ancient DNA refers to genetic material recovered from long-deceased or ancient samples and is a special context rather than a general description of an individual’s genetic makeup.