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[[Image:lighterstill.jpg]][[Image:Sexualitysmall.jpg|right|frame]]
[[Image:lighterstill.jpg]][[Image:Sexuality.jpg|right|frame]]
<center>For lessons on the topic of '''''Sexuality''''', [http://nordan.daynal.org/wiki/index.php?title=Category:Sexuality follow this link].
<center>For lessons on the topic of '''''Sexuality''''', [[Sexuality]] [http://nordan.daynal.org/wiki/index.php?title=Category:Sexuality follow this link].
'''Sexuality''' refers to a biologic state where reproduction is characterized by some manner of [[Sexual Intercourse|sexual union]] between the male and female of a species. This processes enables the passing of a combination of [[Genetics|genetic]] [[material]] to offspring, resulting in [[creativity|creative]] diversity. The main two processes are: [[meiosis]], involving the halving of the number of [[chromosome]]s; and [[fertilization]], involving the [[fusion]] of two gametes and the restoration of the original number of chromosomes. During meiosis, the chromosomes of each pair usually cross over to achieve genetic recombination.
'''Sexuality''' refers to a biologic state where reproduction is characterized by some manner of [[Sexual Intercourse|sexual union]] between the male and female of a species. This processes enables the passing of a combination of [[Genetics|genetic]] [[material]] to offspring, resulting in [[creativity|creative]] diversity. The main two processes are: [[meiosis]], involving the halving of the number of [[chromosome]]s; and [[fertilization]], involving the [[fusion]] of two gametes and the restoration of the original number of chromosomes. During meiosis, the chromosomes of each pair usually cross over to achieve genetic recombination.
The [[evolution]] of [http://www.biolreprod.org/ sexual reproduction] is a major puzzle. The first [http://proxy.arts.uci.edu/~nideffer/Hawking/early_proto/orgel.html] Sexual reproduction is the primary method of reproduction for the vast majority of macroscopic organisms, including almost all [[animal]]s and [[plant]]s. Bacterial conjugation, the transfer of [[DNA]] between two bacteria, is often mistakenly confused with [[sexual reproduction]], because the mechanics are similar.
A major question is why sexual reproduction persists when [[parthenogenesis]] appears in some ways to be a superior form of reproduction. Contemporary [[evolution]]ary [[thought]] proposes some explanations. It may be due to selection pressure on the [[clade]] itself—the ability for a population to radiate more rapidly in response to a changing environment through sexual recombination than parthenogenesis allows. Alternatively, sexual reproduction may allow for the "ratcheting" of evolutionary speed as one clade competes with another for a limited resource.
A major question is why sexual reproduction persists when [[parthenogenesis]] appears in some ways to be a superior form of reproduction. Contemporary evolutionary thought proposes some explanations. It may be due to selection pressure on the [[clade]] itself—the ability for a population to radiate more rapidly in response to a changing environment through sexual recombination than parthenogenesis allows. Alternatively, sexual reproduction may allow for the "ratcheting" of evolutionary speed as one clade competes with another for a limited resource.
==Plants==
==Plants==
===Flowering plants===
===Flowering plants===