Female Topics

• sweat glands
• mammary glands
• egg cells
• x chromosomes
• human females
• female symbols
• land plants
• female plants
• individual cannot reproduce sexually without access
• reproduction system
• greek script
• sporophytes
• roll sex
• breast size
• sex symbols
• spermatozoon
• males and females
• greek names
• gametes
• fatty tissue

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Female, Female

The ova are defined as the larger gametes in a heterogamous reproduction system, while the smaller, usually motile gamete, the spermatozoon, is produced by the male. A female individual cannot reproduce sexually without access to the gametes of a male (an exception is parthenogenesis). Some organisms can reproduce both sexually and asexually.

Other than the defining difference in the type of gamete produced, differences between males and females in one lineage cannot always be predicted by differences in another. The concept is not limited to animals; egg cells are produced by chytrids, diatoms, water moulds and land plants, among others. In land plants, female and male designate not only the egg- and sperm-producing organisms and structures, but also the structures of the sporophytes that give rise to male and female plants.

The mammary glands are modified sweat glands that produce milk, which is used to feed the young during the period of time shortly after birth. Only mammals have the capacity to produce milk. The presence of mammary glands is most obvious on humans, due to the tendency of the female human body to store large amounts of fatty tissue near the nipples, resulting in prominent breasts, although today some human females also surgically augment their breast size. However, mammary glands are present in all mammals, although they are vestigial in the male of the species.

To compensate for the difference in size, one of the female's X chromosomes is randomly inactivated in each cell. In birds, by contrast, it is the female who is heterozygous and carries a Z and a W chromosome whilst the male carries two Z chromosomes.

According to Schott Schott GD. Sex, drugs, and rock and roll: Sex symbols ancient and modern: their origins and iconography on the pedigree.BMJ 2005;331:1509-1510 (24 December), doi:10.1136/bmj.331.7531.1509 , "The most established view is that the male and female symbols "are derived from contractions in Greek script of the Greek names of these planets, namely Thouros (Mars) and Phosphoros (Venus). These derivations have been traced by Renkama Renkema HW. Oorspong, beteekenis en toepassing van de in de botanie gebuikelijke teekens ter aanduiding van het geslacht en den levensduur. In: Jeswiet J, ed. Gedendenkboek J Valckenier Suringar. Wageningen: Nederlandsche Dendrologische Vereeniging, 1942: 96-108.

These may be genetic or environmental, or may naturally change during the course of an organism's life. Although most species with male and female sexes have individuals that are either male or female, hermaphroditic animals have both male and female reproductive organs.

During reproduction, a male can give either an X sperm or a Y sperm, while a female can only give an X egg. A Y sperm and an X egg produce a boy, while an X sperm and an X egg produce a girl. The ZW sex-determination system, where males have a ZZ (as opposed to ZW) sex chromosome may be found in birds and some insects and other organisms. Members of Hymenoptera, such as ants and bees, are determined by haplodiploidy, where most males are haploid and females and some sterile males are diploid.

Other species (such as the goby) are capable of transforming, as adults, from one sex to the other in response to local reproductive conditions (such as a shortage of males). In humans and most mammals, sex is determined chromosomally -- a Y sperm will produce a male offspring and an X sperm a female.

Source: Wikipedia > Female