Actions

::Reproduction

::concepts

First::asexual    Sexual::organism    Species::title    Cells::number    Produce::plant    Meiosis::sperm

{{#invoke:Hatnote|hatnote}}

  1. REDIRECT
    Production of new individuals along a leaf margin of the miracle leaf plant (Kalanchoe pinnata). The small plant in front is about 1 cm (0.4 in) tall. The concept of "individual" is obviously stretched by this asexual reproductive process.

Reproduction (or procreation) is the biological process by which new individual organisms – "offspring" – are produced from their "parents". Reproduction is a fundamental feature of all known life; each individual organism exists as the result of reproduction. There are two forms of reproduction: asexual and sexual.

In asexual reproduction, an organism can reproduce without the involvement of another organism. Asexual reproduction is not limited to single-celled organisms. The cloning of an organism is a form of asexual reproduction. By asexual reproduction an organism creates a genetically similar or identical copy of itself. The evolution of sexual reproduction is a major puzzle for biologists. The two-fold cost of sex is that only 50% of organisms reproduce<ref>Ridley M (2004) Evolution, 3rd edition. Blackwell Publishing, p. 314.</ref> and organisms only pass on 50% of their genes.<ref name="maynard">John Maynard Smith The Evolution of Sex 1978.</ref>

Sexual reproduction typically requires the sexual interaction of two specialized organisms, called gametes, which contain half the number of chromosomes of normal cells and are created by meiosis, with typically a male fertilizing a female of the same species to create a fertilized zygote. This produces offspring organisms whose genetic characteristics are derived from those of the two parental organisms.


Reproduction sections
Intro  Asexual reproduction  Sexual reproduction  Same-sex reproduction   Reproductive strategies   Asexual vs. sexual reproduction  Life without reproduction  Lottery principle  See also  Notes  References  Further reading  External links  

PREVIOUS: IntroNEXT: Asexual reproduction
<<>>