biol es
61freeze fracturing — Biol. a method of preparing a biological specimen for electron microscopic study by rapid freezing, cleaving with a sharp knife or razor, and then covering with a thin layer of metal to make the internal structural planes visible. Also, freeze… …
62germ cell — Biol. the sexual reproductive cell at any stage from the primordial cell to the mature gamete. [1850 55] * * * …
63ground substance — Biol. 1. Also called matrix. the homogeneous substance in which the fibers and cells of connective tissue are embedded. 2. Also called hyaloplasm. the clear portion of the cell cytoplasm; cytosol. [1880 85] * * * ▪ biochemistry an amorphous …
64hair cell — Biol. an epithelial cell having hairlike processes, as that of the organ of Corti. [1885 90] * * * …
65hopeful monster — Biol. a hypothetical individual organism that, by means of a fortuitous macromutation permitting an adaptive shift to a new mode of life, becomes the founder of a new type of organism and a vehicle of macroevolution. [1933; phrase introduced by… …
66inclusive fitness — Biol. the fitness of an individual organism as measured in terms of the survival and reproductive success of its kin, each relative being valued according to the probability of shared genetic information, an offspring or sibling having a value of …
67intermediate host — Biol. the host in which a parasite undergoes development but does not reach sexual maturity. [1875 80] * * * …
68kin selection — Biol. a form of natural selection that favors altruistic behavior toward close relatives resulting in an increase in the altruistic individual s genetic contribution to the next generation. * * * …
69life history — Biol. 1. the series of living phenomena exhibited by an organism in the course of its development from inception to death. 2. See life cycle (def. 1). [1865 70] * * * …
70mast cell — Biol. a large granular cell, common in connective tissue, that produces heparin, histamine, and serotonin. [1885 90; partial trans. of G Mastzelle, equiv. to Mast fattening of animals for slaughter, MAST2 + Zelle cell] * * * ▪ biology… …
