homology

2 ENTRIES FOUND:

ho·mol·o·gy

noun \hō-ˈmä-lə-jē, hə-\
plural ho·mol·o·gies

Definition of HOMOLOGY

1
:  a similarity often attributable to common origin
2
a :  likeness in structure between parts of different organisms (as the wing of a bat and the human arm) due to evolutionary differentiation from a corresponding part in a common ancestor — compare analogy
b :  correspondence in structure between a series of parts (as vertebrae) in the same individual
3
:  similarity of nucleotide or amino acid sequence (as in nucleic acids or proteins)
4
:  a branch of the theory of topology concerned with partitioning space into geometric components (as points, lines, and triangles) and with the study of the number and interrelationships of these components especially by the use of group theory —called also homology theory — compare cohomology

First Known Use of HOMOLOGY

circa 1656

Other Biochemistry Terms

bile, biodegradable, capsaicin, keratin, metabolism

ho·mol·o·gy

noun \hō-ˈmäl-ə-jē, hə-\   (Medical Dictionary)
plural ho·mol·o·gies

Medical Definition of HOMOLOGY

1
a : likeness in structure between parts of different organisms due to evolutionary differentiation from the same or a corresponding part of a remote ancestor—compare analogy, homomorphy b : correspondence in structure between different parts of the same individual
2
a : the relation existing between chemical compounds in a series whose successive members have in composition a regular difference especially of one carbon and two hydrogen atoms CH2 b : the relation existing among elements in the same group of the periodic table c : similarity of nucleotide or amino acid sequence (as in nucleic acids or proteins)

homology

noun    (Concise Encyclopedia)

Similarity of the structure, physiology, or development of different species of organisms based on their descent from a common evolutionary ancestor. Analogy, by contrast, is a functional similarity of structure that is based not on common evolutionary origins but on mere similarity of use. The forelimbs of such widely differing mammals as humans, bats, and deer are homologous; the form of construction and the number of bones in each are practically identical and represent adaptive modifications of the forelimb structure of their shared ancestor. The wings of birds and insects, on the other hand, are merely analogous; they are used for flight in both types of organisms but do not share a common ancestral origin.

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