Sex differences in humans have been studied in a variety of fields. In humans, biological sex consists of five factors present at birth: the presence or absence of the SRY gene an intronless sex-determining gene on the Y chromosome , the type of gonads , the sex hormones , the internal reproductive anatomy such as the uterus , and the external genitalia. Phenotypic sex refers to an individual's sex as determined by their internal and external genitalia, expression of secondary sex characteristics, and behavior. The sex of the individual can be defined in different ways, giving rise to different conceptual frameworks about what determines sex. A subset of such differences is hypothesized to be the product of the evolutionary process of sexual selection.
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Sexual intercourse or coitus or copulation is sexual activity typically involving the insertion and thrusting of the penis into the vagina for sexual pleasure , reproduction , or both. There are different views on what constitutes sexual intercourse or other sexual activity , which can impact on views on sexual health. Various jurisdictions place restrictions on certain sexual acts, such as incest , sexual activity with minors , prostitution , rape , zoophilia , sodomy , premarital and extramarital sex. Religious beliefs also play a role in personal decisions about sexual intercourse or other sexual activity, such as decisions about virginity ,   or legal and public policy matters. Religious views on sexuality vary significantly between different religions and sects of the same religion, though there are common themes, such as prohibition of adultery. Reproductive sexual intercourse between non-human animals is more often called copulation , and sperm may be introduced into the female's reproductive tract in non-vaginal ways among the animals, such as by cloacal copulation.
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Malaka Gharib. That's one of the central questions in The Pleasure Gap: American Women and the Unfinished Sexual Revolution , a book published this month by public health researcher and journalist Katherine Rowland. Rowland explores why American women aren't happy with their sex lives — and what they can do about it. A contributing factor, noted the researchers, was the lasting psychological effects of sexual trauma. Your purchase helps support NPR programming. The Pleasure Gap highlights how desire and the mind are linked for women.
View research View latest news Sign up for updates. An experiment was conducted to examine the stereotypes about human sexuality held by persons of different sex-role orientations. Sex-typed and androgynous subjects were given bogus information about the sexual experience of another person. This other person was either a male or a female and either high or low in sexual experience. The subjects were then shown some erotic slides and asked to predict how sexually aroused the target person would be by viewing these stimuli. Additionally, the subjects were asked to rate the target person on traits of a sexual and evaluative nature. The results showed, as predicted, that the sexual experience of a female target influences how much sexual arousal is attributed to her. Female targets of high experience were attributed more arousal than inexperienced female targets. For male targets, no such difference was found. Ratings of the targets on an evaluative dimension revealed a double standard: Sexually experienced females were rated lower than were inexperienced females; no difference was found for male targets.