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In
biology the sexual maturity (also called: adulthood or
maturity) is the period in the
life cycle of a
living being in which physical
growth has stopped or reached a certain stage of development and the
reproductive organs are
completely formed and able to produce the
gametes (see:
meiosis).
It may also be accompanied by the outward emergence of
secondary sexual
characteristics which distinguish the
immature
organism from its adult
form and often lead it to an increase in sexual
dimorphism. For example,
human children have smooth faces, but adult males have hairy beard
while adult females do not.
After sexual maturity is achieved, it is possible for some organisms to
become sterile, or even to change their
sex. Moreover some organism
display most or all of the
characteristics of the adult form without
being sexually mature. Inversely, it is as well possible for some
apparently juvenile
immature form to
reproduce (see
neoteny).
But a considerable number of
multicellular organisms are not able to sexually reproduction, they
can only reproduce vegetatively
while Bacteria and other
unicellular living organism
reproduce by division (mitosis). |
