Note: There are two distinct methods of reproduction; viz.:
{asexual reproduction} (agamogenesis) and {sexual
reproduction} (gamogenesis). In both cases the new
individual is developed from detached portions of the
parent organism. In asexual reproduction (gemmation,
fission, etc.), the detached portions of the organism
develop into new individuals without the intervention
of other living matter. In sexual reproduction, the
detached portion, which is always a single cell, called
the female germ cell, is acted upon by another portion
of living matter, the male germ cell, usually from
another organism, and in the fusion of the two
(impregnation) a new cell is formed, from the
development of which arises a new individual.
2. That which is reproduced.