| noeud vital | A circumscript region in the lower part of the medulla oblongata, near the apex of the calamus scriptorius, interpreted by M. Flourens (1858) as a nerve centre controlling respiration. Synonym: vital knot, vital node. Origin: Fr. (05 Mar 2000) |
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| electro-vital | Derived from, or dependent upon, vital processes; said of certain electric currents supposed by some physiologists to circulate in the nerves of animals. Source: Websters Dictionary (01 Mar 1998) |
| forced vital capacity | Vital capacity measured with the subject exhaling as rapidly as possible; data relating volume, expiratory flow, and time form the basis for other pulmonary function tests, e.g., flow-volume curve, forced expiratory volume, forced expiratory time, forced expiratory flow. (05 Mar 2000) |
| active centre | The part of a macromolecule at which a substrate or ligand, upon binding, produces biological activity; for an enzyme, this is the catalytic centre, the site on an enzyme that catalyses the reaction. (05 Mar 2000) |
| anospinal centre | The centre in the spinal cord that controls the contraction of the anal sphincter. (05 Mar 2000) |
| asymmetric centre | <chemistry> Same as a chiral centre, a tetrahedral carbon atom that bears four different substituents. (09 Jan 1998) |
| Broca's centre | The posterior part of the inferior frontal gyrus of the left or dominant hemisphere, corresponding approximately to Brodmann's area 44; Broca identified this region as an essential component of the motor mechanisms governing articulated speech. Synonym: Broca's area, Broca's field, motor speech centre. (05 Mar 2000) |
| Budge's centre | The preganglionic motor neurons in the first thoracic segment of the spinal cord which give rise to the sympathetic innervation of the dilator muscle of the eye's pupil. Synonym: Budge's centre. (05 Mar 2000) |
| vasomotor centre | Diffuse area of the reticular formation in the lateral medulla containing neurons that control vascular tone; consists of separate vasodepressor and vasopressor areas. (05 Mar 2000) |
| reaction centre | <plant biology> The site in the chloroplast that receives the energy trapped by chlorophyll and accessory pigments and initiates the electron transfer process. A photosynthetic complex containing chlorophyll (or bacteriochlorophyll) and other components, within which occurs the initial electron transfer reactions of photophosphorylation. (09 Oct 1997) |
| germinal centre | Areas within lymph nodes where B lymphocytes rapidly divide. (09 Oct 1997) |
| germinal centre kinase | <enzyme> A human ste20 homolog; mw 97 kD; has been sequenced Registry number: EC 2.7.10.- Synonym: germinal centre kinase gck, gc kinase, bl44 gene product (26 Jun 1999) |
| germinal centre of Flemming | The lightly staining centre in a lymphatic nodule in which the predominant cells are large lymphocytes and macrophages. Synonym: reaction centre. (05 Mar 2000) |
| catalytic centre | See: active centre. (05 Mar 2000) |
| cell centre | Microtubule organising centre of the cell, the pericentriolar region. (18 Nov 1997) |