Final answer:
Paralogous genes are those that differ slightly in sequence and originated from a gene duplication event within the same organism. They are a type of homologous genes, in contrast to orthologous genes that are found in different species but evolved from a common ancestor.
Step-by-step explanation:
Genes that may differ slightly in sequence but were derived by duplication during evolution are called Paralogous genes. These genes arise from gene duplication within the same organism, leading to a family of related genes within a single genome. Homologous genes, on the other hand, are genes that share a common ancestor, and they can be further classified into orthologous genes, which are homologous genes found in different species that evolved from a common ancestral gene, and paralogous genes, which are homologous genes that are found within the same species but have diverged after a duplication event. In the context of blood type genetics, the ABO blood group system shows how different alleles (A, B, and O) of a single gene can determine the blood type of an individual. A person may inherit identical alleles (homozygous) or two different alleles (heterozygous), leading to the phenotypic expression of traits such as blood type A (genotype AA or AO), B (genotype BB or BO), AB, or O (genotype OO).
Paralogous genes are genes that may differ slightly in sequence but were derived by duplication during evolution. These genes are found within the same organism and often have slightly different functions. Paralogous genes can provide important insights into how gene duplication and evolution have shaped biological diversity.