Sex determination mechanisms used in genetics a cross

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This article’s lead section does not adequately summarize key points of its contents. The symbol of the Roman goddess Venus is commonly used to represent the female sex and is the alchemical symbol for copper. Barring rare medical conditions, most female mammals, including female humans, have two X chromosomes. There is no single genetic mechanism behind sex differences in different species and the existence of two sexes seems to have evolved multiple times independently in different evolutionary lineages. Oogamous species, which include humans in which the female gamete is very much larger than the male and has no ability to move.

Oogamy is a form of anisogamy. 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 word female comes from the Latin femella, the diminutive form of femina, meaning “woman”. It is not etymologically related to the word male, but in the late 14th century the spelling was altered in English to parallel the spelling of male.

Adult female and male with clean-shaven pubic regions. A distinguishing characteristic of the class Mammalia is the presence of mammary glands. The mammary glands are modified sweat glands that produce milk, which is used to feed the young for some time after birth. The sex of a particular organism may be determined by a number of factors. 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, the male contributes either an X sperm or a Y sperm, while the female always contributes an X egg.

The young of some species develop into one sex or the other depending on local environmental conditions, e. Look up female in Wiktionary, the free dictionary. Wikimedia Commons has media related to Females. English Words from Latin and Greek Elements. The Metaphysics of Sex in a Changing World!