Knight — 18 — Dictionary 



Biomass. — A general term for any wide group of organisms. 



Biometry. — The branch of science which deals with the ap- 

 plication of statistical methods to biological investigations. 



Bion. — A hypothetical element which was thought to be 

 present in living matter, its function being the control of 

 evolution. 



Biophore. — Weismann postulated that each determinant 

 (gene) is made up of a complex of biophores which he regarded 

 as the smallest ultimate units of living matter. A biophore 

 is the equivalent of the biogen of Verworn. 



Bioplasm. — Protoplasm; living cell substance including the 

 nucleus and cytoplasm. 



Biosystematy. — Taxonomic studies involving cytology and 

 genetics. 



Biotin. — A component of the vitamin B^ complex. 



Biotope. — The smallest natural area or space characterized by 

 a particular environment (Cain, 1944). 



Biotype. — A group of individuals all of one genotype. 



Biparous. — Giving birth to two offspring at a time. 



Birefringent. — Of chromosomes, etc.: having certain types 

 of regular molecular or micellar patterns, usually detectable 

 by the use of polarized light. 



Bisexual. — Hermaphrodite, having both male and female re- 

 productive organs in one individual. 



Bivalent. — Two chromosomes containing approximately the 

 same gene loci which have come together side-by-side at zygo- 

 tene and which are held together by chiasmata or by mutual 

 attraction. See Univalent and Chromatid. 



Blastogenesis. — (i) Germplasm inheritance; the transmission 

 of hereditary characters by the germplasm as distinct from 

 transmission by the cytoplasm, (ii) Reproduction by budding. 



Blastogenic. — Of, or pertaining to, the germplasm. 



Blastomere. — Any one of the cells formed during the first 

 few divisions of the animal egg. 



Blastula. — The stage in the development of the zygote during 

 which the embryo-cells are arranged in the form of a hollow 

 sphere. 



Bleeder. — A hsemophilic individual. 



Blending Characters. — Characters which merge, thus failing 

 to show the clear-cut segregation typical of mendelian heredity. 

 See Blending Inheritance. 



Blending Inheritance. — Inheritance in which clearly defined 

 segregation is lacking in Fg. This is generally due to the 

 presence of multiple factors independently inherited. 



