| homorganic | Produced by the same organs, or by homologous organs. (05 Mar 2000) |
|---|---|
| homosalate | 3,3,5-Trimethylcyclohexyl salicylate;an ultraviolet screening agent for topical application to the skin. (05 Mar 2000) |
| homoscedasticity | Constancy of the variance of a measure over the levels of the factor under study. (05 Mar 2000) |
| homoserine | An amino acid which is used by plants and bacteria to make methionine, threonine, and isoleucine (three of the twenty amino acids used to make proteins). Homoserine is similar to the amino acid serine (another of the twenty amino acids used to make proteins), except it has an extra methylene group. It is also formed when cystathionine is metabolised into the amino acid cysteine (another of the twenty amino acids used to make proteins). (09 Oct 1997) |
| homoserine deaminase | <enzyme> A multifunctional pyridoxal phosphate enzyme. In the final step in the biosynthesis of cysteine it catalyses the cleavage of cystathionine to yield cysteine, ammonia, and 2-ketobutyrate. Chemical name: L-Cystathionine cysteine-lyase (deaminating) Registry number: EC 4.4.1.1 (12 Dec 1998) |
| homoserine dehydratase | <enzyme> A multifunctional pyridoxal phosphate enzyme. In the final step in the biosynthesis of cysteine it catalyses the cleavage of cystathionine to yield cysteine, ammonia, and 2-ketobutyrate. Chemical name: L-Cystathionine cysteine-lyase (deaminating) Registry number: EC 4.4.1.1 (12 Dec 1998) |
| homoserine dehydrogenase | <enzyme> An enzyme that catalyses the reduction of aspartic beta-saemialdehyde to homoserine, which is the branch point in biosynthesis of methionine, lysine, threonine and leucine from aspartic acid. Chemical name: L-Homoserine:NAD(P)+ oxidoreductase Registry number: EC 1.1.1.3 (12 Dec 1998) |
| homoserine lactone | The cyclic ester (i.e., the d-lactone) of homoserine; formed by the reaction of cyanogen bromide on methionyl residues in peptides and proteins. (05 Mar 2000) |
| homosexual | A person sexually attracted to persons of the same sex. Homosexuals include males (gays) and females (lesbians). Homosexual can also be an adjective. (12 Dec 1998) |
| homosexuality | Sexuality directed toward someone of the same sex. (12 Dec 1998) |
| homosexuality, female | Sexual attraction or relationship between females. (12 Dec 1998) |
| homosexuality, male | Sexual attraction or relationship between males. (12 Dec 1998) |
| homospermidine synthetase | <enzyme> Proposed mechanism-schiff base formed between putrescine and its oxidation product, 4-aminobutyraldehyde, then reduced to sym-homospermidine; requires nad Registry number: EC 2.5.1.- Synonym: homospermidine synthase (26 Jun 1999) |
| homosporous | Producing only one kind of spore in the sexual reproductive cycle, and hence one gametophyte which produces both male and female gametes. Compare: heterosporous. (09 Oct 1997) |
| homosteroid | A steroid that has had at least one of the rings in its structure expanded. (05 Mar 2000) |