what are homologues?

Answer 1

If you're talking about genetics they are the two individual chromosomes that form a similar pair. For example each Human cell has 23 homologous pairs of chromosomes, one set derived from each parent.

Answer 2

Also in genetics, homologues are two genes (most often from different species) that share common functions and evolutionary origins.

Answer 3

Webster's English Dictionary defines homologous as:

1a: having the same relative position, value, or structure
1b1: corresponding in structure or function
1b2: of like genic constitution
1c: belonging to or consisting of a chemical series whose members exhibit homology
2: derived from or developed in response to organisms of the same species {~ tissue graft}

The American Heritage Dictionary defines homologous as:
(adj.)Corresponding or similar in position, value, structure, or function.
(adj.)Similar in structure and evolutionary origin, though not necessarily in function, as the flippers of a seal and the hands of a human.
(adj.)Relating to the correspondence between an antigen and the antibody produced in response to it.

According to Wikipedia, Homology may refer to:
* Homology (anthropology), a type of analogy whereby two human beliefs, practices or artefacts share similarities due to genetic or historical connections.
* Homology (biology): structures are said to be homologous if they are alike because of shared ancestry.
* Homology (mathematics), a procedure to associate a sequence of abelian groups or modules with a given mathematical object.
* Homology (sociology), a structural 'resonance' between the different elements making up a socio-cultural whole.
* Homologous series (chemistry), a series of organic compounds with a similar general formula.
* Homology modeling, a method of protein structure prediction

In biology, homologues are things that have a common evolutionary origin but may serve different functions or uses. Homologues correspond in structure and origin, but not necessarily in function.

The wings of bats and the arms of humans are homologues. The foreleg of a horse and the wing of a bird are homologues.

Since they have different origins, the tails of fish and flukes of whales ARE NOT homologues.

Structures similar in appearance or function but not necessarily in origin are "homoplastic" or "analogues".

Answer 4

Things that are similar, but have a different origin.

The tails of fish and flukes of whales, for example. Or the wings of birds and bats.