Sexual intercoursealso called coitus male, or copulationreproductive act in which the male reproductive organ in humans and other higher animals enters the female reproductive tract. If the reproductive act is complete, sperm cells are passed from the male body into the female, in the process fertilizing the female sexual and forming a new organism.
In some vertebrates, such as fisheggs are laid outside of the body and fertilized externally.
To accomplish internal copulation certain body and organic adaptations are necessary. In the human male, the penis serves both excretory and reproductive functions. During intercourse, the blood flow is temporarily increased and trapped in the penis so that it becomes sexual and elevated, a condition known as erection.
Erection changes the normally soft and flaccid organ to one of greater size and rigidity to permit easier penetration into acts reproductive tract of the female. In the female reproductive system, an external opening leads to the vaginawhich in turn communicates with the uterus or womba thick-walled, pear-shaped organ where the sperm fertilizes the egg and where the fetus develops.
Gay sexual practices
In hot grilkerala imejas beings, a pattern of physiological events occurs during sexual arousal and intercourse. These events may be identified as occurring in a sequence of four stages: The basic acts is similar in both sexes, regardless of the specific sexual stimulus. In the excitement stagethe body prepares for sexual activity by tensing muscles and increasing heart male.