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Spore formation
(gcide) | Spore \Spore\ (sp[=o]r), n. [Gr. ? a sowing, seed, from ? to
sow. Cf. Sperm.]
1. (Bot.)
(a) One of the minute grains in flowerless plants, which
are analogous to seeds, as serving to reproduce the
species.
[1913 Webster]
Note: Spores are produced differently in the different
classes of cryptogamous plants, and as regards their
nature are often so unlike that they have only their
minuteness in common. The peculiar spores of diatoms
(called auxospores) increase in size, and at length
acquire a siliceous coating, thus becoming new diatoms
of full size. Compare Macrospore, Microspore,
Oospore, Resting spore, Sphaerospore,
Swarmspore, Tetraspore, Zoospore, and
Zygospore.
[1913 Webster]
(b) An embryo sac or embryonal vesicle in the ovules of
flowering plants.
[1913 Webster]
2. (Biol.)
(a) A minute grain or germ; a small, round or ovoid body,
formed in certain organisms, and by germination giving
rise to a new organism; as, the reproductive spores of
bacteria, etc.
(b) One of the parts formed by fission in certain
Protozoa. See Spore formation, belw.
[1913 Webster]
Spore formation.
(a) (Biol) A mode of reproduction resembling multiple
fission, common among Protozoa, in which the organism
breaks up into a number of pieces, or spores, each of
which eventually develops into an organism like the
parent form. --Balfour.
(b) The formation of reproductive cells or spores, as in
the growth of bacilli.
[1913 Webster] |
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