| genes, overlapping | Genes whose nucleotide sequences overlap to some degree. The overlapped sequences may involve structural or regulatory genes of eukaryotic or prokaryotic cells. (12 Dec 1998) |
|---|---|
| overlapping | <cell biology> In cell locomotion situation in which the leading lamella of one cell moves actively over the dorsal surface of another cell should be distinguished from underlapping. (18 Nov 1997) |
| overlapping gene | <molecular biology> Different genes whose nucleotide coding sequences overlap to some extent. The common nucleotide sequence is read in two or three different reading frames thus specifying different polypeptides. (18 Nov 1997) |
| overlapping reading frame | <molecular biology> Start codons in different reading frames which generate different polypeptides from the same DNA sequence. (09 Oct 1997) |
| androgenic zone | A transient adrenocortical zone present in some rodents at birth, most notably in mice, situated between the zona reticularis and the adrenal medulla; it degenerates in males with the secretion at puberty and in females during their first pregnancy; it slowly enlarges in unmated females after puberty and does not degenerate until middle age; the X zone appears to secrete no hormone. Synonym: androgenic zone. Misnomer for the foetal adrenal cortex of primates. Synonym: foetal reticularis. (05 Mar 2000) |
| arcuate zone | The inner third of the basilar membrane of the cochlear duct extending from the tympanic lip of the osseous spiral lamina to the outer pillar cell of the spiral organ (of Corti). Synonym: zona arcuata, zona tecta. (05 Mar 2000) |
| Barnes' zone | The lower fourth of the pregnant uterus, attachment of the placenta to any part of which may cause dangerous haemorrhage. Synonym: cervical zone. (05 Mar 2000) |
| buffer zone | <ecology> An area of land separating two distinct land uses that acts to soften or mitigate the effects of one land use on the other. (09 Oct 1997) |
| capillary zone electrophoresis | A method for separating molecules extremely rapidly based on their electrophoretic mobility. (05 Mar 2000) |
| vascular zone | An area in the external acoustic meatus where a number of minute blood vessels enter from the mastoid bone. Synonym: spongy spot, zona vasculosa. (05 Mar 2000) |
| mantle zone | A layer of small B lymphocytes surrounding the paler-staining germinal centres of lymphoid follicles. (05 Mar 2000) |
| Marchant's zone | The area on the sphenoid and occipital bones at the base of the skull from which the dura mater is readily detached. (05 Mar 2000) |
| marginal zone | The outer, nonnuclear layer of the embryonic neural tube; into its fibrous network grow the longitudinal nerve fibres which eventually become the white matter of the cord and brain stem. Synonym: marginal zone. (05 Mar 2000) |
| vermilion zone | The red margin of the upper and lower lip that commences at the exterior edge of the intraoral labial mucosa ("moist line") and extends outward, terminating at the extraoral labial cutaneous junction; a thinly keratinised type of stratified squamous epithelium deeply penetrated by well-vascularised dermal papillae which show through the translucent epidermis to impart the typical red appearance of the lips. Synonym: vermilion zone, vermilion transitional zone. (05 Mar 2000) |
| recruitment zone | <cell biology> Region of cytoplasm in the rear third of a moving amoeba where endoplasm is recruited from ectoplasm. (18 Nov 1997) |