Knight — 74 — Dictionary 



Homology. — Similarity of structures due to similarity of 

 origin. N. Homologue. Adj. Homologous. 



Homology, Residual. — A degree of affinity still existing 

 between once truly homologous chromosomes, which will now 

 only rarely permit crossing-over between them (Stephens). 

 cf. Homoeologous Chromosomes. 



Homomorphic. — Of chromosome pairs: morphologically in- 

 distinguishable. 0pp. Heteromorphic. 



Homomorphic Incompatibility. — Incompatibility (q.v.) 

 which is not dependent for its action on morphological variation. 



Homonculus, Homunculus. — The miniature foetus erro- 

 neously thought to be present in a human spermatozoon. 



Homoosis. — The production in one particular region of an in- 

 dividual, of an appendage normally occurring in a different 

 region of the individual's body. 



Homophytic. — Monoecious, q.v. 



Homoplasy. — Similarity due to adaptation to common func- 

 tions or similar environments. Adj. Homoplastic. 



Homopolar. — Of pairing chromosomes: having the attrac- 

 tion force evenly distributed throughout the length of the 

 chromosome (as at zygotene). 



Homosynapsis. — Pairing of homologous chromosomes, cf. 

 Heterosynapsis. 



Homotype Division. — Homotypic Division, q.v. 



Homotypic Division. — The second, or non-reductional, 

 meiotic division. 



Homozygosis. — The state of having any specific gene(s) 

 in the double condition so that the organism is pure-breeding 

 for that (or those) particular gene(s) since all its gametes 

 contain it (or them). 



Homozygosis Frequency. — The frequency with which one 

 allele of a heterozygous gene-pair becomes homozygous in the 

 succeeding generation, the gene-pair concerned being situated 

 in attached X-chromosomes. 



Homozygote. — An organism having any specified gene, or 

 genes homozygous. See Homozygosis and Homozygous. 



Homozygotes, Proportion of. — See Appendix 1. 



Homozygotization. — The rendering of a species, group, etc. 

 homozygous. 



Homozygous. — Of an organism: having any specified gene 

 or genes, present in the double condition (AA as distinct from 

 Aa). See Homozygosis. 



