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Tag Wiki 'Gamete'.

A gamete (; from γαμετή gamete from gamein "to marry") is a haploid cell that fuses with another haploid cell during in that sexually reproduce and possess only one set of dissimilar chromosomes. Gametes are an organism's reproductive cells, also referred to as sex cells. In species that produce two morphologically distinct types of gametes, and in which each individual produces only one type, a is any individual that produces the larger type of gamete—called an — and a produces the smaller -like type—called a . Sperm cells or spermatozoon are small and motile due to the flagellum, a tail-shaped structure that allows the cell to propel and move. In contrast, each egg cell or ovum is relatively large and non-motile. In short a gamete is an egg cell (female gamete) or a sperm (male gamete). Ova mature in the ovaries of females and sperm develop in the testes of males. During fertilization, a spermatozoon and ovum unite to form a new diploid organism. Gametes carry half the genetic information of an individual, one of each type, and are created through , in which a germ cell undergoes two fissions, resulting in the production of four gametes. In biology, the type of gamete one produces determines the classification of their sex.

This is an example of or , the condition in which females and males produce gametes of different sizes (this is the case in humans; the human ovum has approximately 100,000 times the volume of a single human sperm cell). In contrast, is the state of gametes from both sexes being the same size and shape, and given arbitrary designators for . The name gamete was introduced by the German cytologist Eduard Strasburger.

is the process of female gamete formation in animals. This process involves (including meiotic recombination) occurring in the diploid primary to produce the haploid . is the process of male gamete formation in animals. This process also involves meiosis occurring in the diploid primary to produce the haploid .

In contrast to a gamete, the diploid of an individual contain one copy of the set from the sperm and one copy of the chromosome set from the egg cell; that is, the cells of the offspring have genes expressing characteristics of both the father and the mother. A gamete's chromosomes are not exact duplicates of either of the sets of chromosomes carried in the diploid chromosomes, and may undergo random mutations resulting in modified DNA and subsequently, new proteins and .

Sex determination in mammals and birds
and most mammals use the XY sex-determination system in which a normal ovum can carry only an whereas a sperm may carry either an X or a Y , while a non-normal sperm cell can end up carrying either no sex-defining chromosomes, an XY pair, or an XX pair; thus the male sperm determines the of any resulting . If the zygote has two X chromosomes it will develop into a female, if it has an X and a Y chromosome, it will develop into a male.
(2009). 9781429223188, Macmillan. .

For birds, the female ovum determines the sex of the offspring, through the ZW sex-determination system.

Artificial gametes
Artificial gametes, also known as In vitro derived gametes (IVD), stem cell-derived gametes (SCDGs), and In vitro generated gametes (IVG), are gametes derived from . Research shows that artificial gametes may be a reproductive technique for same-sex male couples, although a would still be required for the gestation period. Women who have passed may be able to produce eggs and bear genetically related children with artificial gametes. Robert Sparrow wrote, in the Journal of Medical Ethics, that embryos derived from artificial gametes could be used to derive new gametes and this process could be repeated to create multiple human generations in the laboratory. This technique could be used to create for medical applications and for studying the heredity of . Additionally, this technique could be used for human enhancement by selectively breeding for a desired genome or by using technology to create enhancements that have not arisen in nature.

which reproduce sexually also have gametes. However, since plants have an alternation of diploid and haploid generations some differences exist. In , the use to produce a haploid generation which produce gametes through mitosis. The female haploid is called the and is produced by the ovary of the flower. When mature, the haploid ovule produces the female gamete which are ready for fertilization. The male haploid is and is produced by the , when pollen lands on a mature stigma of a flower it grows a down into the flower. The haploid pollen then produces sperm by mitosis and releases them for fertilization.

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