homologous

ho·mol·o·gous  (h-ml-gs, h-)

adj.

1. Corresponding or similar in position, value, structure, or function.

2. Biology Similar in structure and evolutionary origin, though not necessarily in function, as the flippers of a seal and the hands of a human.

3. Immunology Relating to the correspondence between an antigen and the antibody produced in response to it.

4. Genetics Having the same morphology and linear sequence of gene loci as another chromosome.

5. Chemistry Belonging to or being a series of organic compounds each successive member of which differs from the preceding member by a constant increment, especially by an added CH₂ group.

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[From Greek homologos, agreeing : homo-, homo- + logos, word, proportion; see leg- in Indo-European roots.]

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homologous [hom-ol-log-uss]

Adjective

1. having a related or similar position or structure

2. Biol (of organs and parts) having the same origin but different functions: the wing of a bat and the arm of a monkey are homologous [Greek homos same + logos ratio]

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homologous  (h-ml-gs)

1. Similar in structure and evolutionary origin but having different functions, as a human's arm and a seal's flipper.

2. Being one of a pair of chromosomes, one from the female parent and one from the male parent, that have genes for the same traits in the same positions. Genes on homologous chromosomes may not have the same form, however. For example, one chromosome in a pair of homologous chromosomes may contain a gene for brown eyes, and the other a gene for blue eyes. Human females have 23 pairs of homologous chromosomes (including the two X chromosomes), while human males have 22 because the Y chromosome is not paired.

3. Belonging to or being a series of organic compounds, each successive member of which differs from the preceding member by a constant increment, especially by an added CH₂ group. The alkanes (methane, ethane, propane, and others) are a homologous series of compounds.

4. Involving organisms of the same species, as in grafted body tissues.

Thesaurus

Adj.	1.	homologous - having the same evolutionary origin but not necessarily the same function; "the wing of a bat and the arm of a man are homologous" biological science, biology - the science that studies living organisms analogous - corresponding in function but not in evolutionary origin; "the wings of a bee and those of a hummingbird are analogous" heterologic, heterological, heterologous - not corresponding in structure or evolutionary origin
	2.	homologous - corresponding or similar in position or structure or function or characteristics; especially derived from an organism of the same species; "a homologous tissue graft" autologous - derived from organisms of the selfsame individual; "autologous blood donation" heterologous - derived from organisms of a different but related species; "a heterologous graft"