APPENDIX I 



Gene [continued) 



4. A unit of physiological action (not rigorously applicable in all 



cases). 

 Its changes may be inter-genic and structural or intra-genic and 



molecular. Darlington 1932. v. Mutation. 

 Gene Dosage, the number of times a gene is present in the nucleus of 



a given cell or organism. 

 Gene Dosage Compensation, the equal physiological effectiveness of 

 one gene in the X chromosome of the male to two genes in the 

 X chromosomes of the female. Mnllcr 1932. 

 Gene Frequency, the proportion of the total chromosomes of a popu- 

 lation which contain a given allelomorph of a gene. 

 Gene Mutation, v. Mutation. 



Mutable (Unstable) Gene, one liable to frequent mutation. 

 Super-Gene, a group of genes acting as a mechanical unit in par- 

 ticular aUelomorphic combinations. 

 Genetic, pertaining to or analogous with Heredity. Bateson 1906. 

 Genetic Equilibrium, the condition of a population in which successive 

 generations consist of the same genotypes with the same frequencies, 

 in respect of particular genes or arrangements of genes. 

 Genetic System, the reproductive and hereditary organization of 



mating group. Darlington 1940. 

 Genetics, the science of heredity including the study of its chemical 

 foundation, its developmental expression and its bearings on varia- 

 tion, selection, adaptation, evolution, animal and plant breeding and 

 the activities of man. Bateson 1906. 

 Genome, Chromosome Set, especially as considered genetically. Winkler 



1916. 

 Genotype, i. The kind or type of the hereditary properties of an indi- 

 vidual. Jo/w/zn5en 1909. 

 2. The hereditary materials considered as a unit. 

 Genotypic Control, the control of chromosome behaviour by the 

 genotype, in contrast to Structural Control, especially at meiosis 

 through the effects of dissimilarity of the pairing chromosomes in 

 Hybrids. Darlington 1932. 

 Genotypic Environment, v. Environment. 

 Germ Cell, Gamete. 



Germ Plasm (Keimplasma), the hereditary materials, i.e. the aggregate 

 of self-propagating particles, which are transmitted to the offspring 

 through the germ cells, v. Gene, Protoplasm, Virus. Weisniann 

 1892. 



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