| secondary egg membrane | See: egg membrane. (05 Mar 2000) |
|---|---|
| homolecithal egg | An egg in which the total amount of yolk is small and fairly uniformly distributed throughout the cytoplasm. Synonym: isolecithal egg. (05 Mar 2000) |
| Dorset's culture egg medium | A medium for cultivating Mycobacterium tuberculosis; it consists of the whites and yolks of four fresh eggs and a solution of sodium chloride. (05 Mar 2000) |
| isolecithal egg | An egg in which the total amount of yolk is small and fairly uniformly distributed throughout the cytoplasm. Synonym: isolecithal egg. (05 Mar 2000) |
| telolecithal egg | An egg containing a relatively large quantity of deutoplasm concentrated at the abapical pole; e.g., egg's of reptiles and birds. (05 Mar 2000) |
| tertiary egg membrane | See: egg membrane. (05 Mar 2000) |
| egg | A structure which the females of certain animal species lay as a means of reproduction, it contains a fertilized zygote and nutrition in the form of yolk for the developing offspring, sometimes contains other substances (e.g., the white of a hen's egg), sometimes surrounded by a protective outer shell. (09 Oct 1997) |
| egg albumin | <protein> A major protein constituent of egg white. A phosphoprotein of 386 amino acids (44 kD) with one N linked oligosaccharide chain. Synthesis is stimulated by oestrogen. The gene, of which there is only one in the chicken genome, has eight exons and is of 7.8 kbase, it was one of the first genes to be studied in this sort of detail. (18 Nov 1997) |
| egg-bird | <zoology> A species of tern, especially. The sooty tern (Sterna fuliginosa) of the West Indies. In the Bahama Islands the name is applied to the tropic bird, Phaethon flavirostris. Source: Websters Dictionary (01 Mar 1998) |
| egg cell | The unfertilised ovum. (05 Mar 2000) |
| egg cluster | One of the clumps of cells resulting from the breaking up of the gonadal cords in the ovarian cortex; these clumps later develop into primary ovarian follicles. (05 Mar 2000) |
| egg coat | A layer of glycoproteins and other stuff which surrounds an egg (ovum), just outside of the egg's cell membrane. The coat protects the egg, and for organisms which practice external fertilization (fertilization outside of the parents' bodies) it can help prevent the sperm of other species from entering the egg. For the eggs of mammals, the egg coat is called the zona pellucida and for sea urchins (a popular study organism for developmental biologists) it is called the vitelline layer. (09 Oct 1997) |
| egg donation | Donation of an ovum by one woman to another who attempts to become pregnant by in vitro fertilization. (09 Oct 1997) |
| egg drop syndrome | <syndrome> A disease of chickens caused by an adenovirus and characterised by production of soft-shelled and shell-less eggs in apparently healthy birds. (05 Mar 2000) |
| egg membrane | The investing envelope of the ovum; a primary egg membrane is produced from ovarian cytoplasm (e.g., a vitelline membrane); a secondary egg membrane is the product of the ovarian follicle (e.g., the zona pellucida); a tertiary egg membrane is secreted by the lining of the oviduct (e.g., a shell). (05 Mar 2000) |