Human reproduction is the reproduction of humans. It is a form of sexual reproduction, by sexual intercourse between human males and females. In the sexual intercourse, interaction between the male reproductive system and the female reproductive system results in pregnancy, which is followed by childbirth

Anatomy

See: Human reproductive system

The human male

The male reproductive system contains two main divisions: the penis, and the testes, the latter of which is where sperm are produced. In humans, both of these organs are outside the abdominal cavity. Having the testes outside the abdomen best facilitates temperature regulation of the sperm, which require specific temperatures to survive.

Sperm are the smaller than the female ovum, and live approximately 2 weeks after production, requiring males to produce them continuously from the time of sexual maturity until death. Prior to ejaculation the produced sperm are stored in the seminal vesicle, a small gland that is located just behind the bladder.
A sperm cell is motile and swims via chemotaxis, using its flagellum to propel itself towards the ovum.

The human female

The female reproductive system likewise contains two main divisions: the vagina and uterus, which act as the receptacle for the sperm, and the ovaries, which produce the female's ova. The vagina is attached to the uterus through the cervix, while the uterus is attached to the ovaries via the Fallopian tubes. At certain intervals, the ovaries release an ovum, which passes through the fallopian tube into the uterus.

If, in this transit, it meets with sperm, the sperm penetrate and merge with the egg, fertilizing it. The fertilization usually occurs in the oviducts, but can happen in the uterus itself. The zygote then implants itself in the wall of the uterus, where it begins the processes of embryogenesis and morphogenesis. When developed enough to survive outside the womb, the cervix dilates and contractions of the uterus propel the foetus through the birth canal, which is the vagina.

The ova, which are the female sex cells, are much larger than the sperm and are normally formed with in the ovaries of the fetus before its birth. They are mostly fixed in location with in the ovary until their transit to the uterus, and contain nutrients for the later zygote and embryo. Over a regular interval, in response to hormonal signals, a process of oogenesis matures one ovum which is released and sent down the Fallopian tube. If not fertilized, this egg is flushed out of the system through menstruation.

Process

Human reproduction is a long process, starting with sexual intercourse, followed by nine months of pregnancy before childbirth. Many years of parental care is required in order to finish with a mature human being.