All living things, including humans, reproduce; it's one of the things that set us apart from nonliving matter. And because all living things eventually die, new creatures of the same kind must constantly be born to perpetuate a particular species. Interestingly, although the reproductive system is essential to keeping a species alive, unlike other body systems, it is not essential to keeping an individual being alive.

Males and females both have organs in their bodies that make sex cells. In males they are called sperm cells and in females they are called egg cells.

When the two types of sex cells meet under certain conditions, they produce a zygote. This process is called fertilization.

After the second week the zygote becomes an embryo until the eighth week of pregnancy. Then the offspring is called a foetus.

A human baby is usually born after about forty weeks of development.

Female Reproductive System

The female reproductive organs include the vagina (a muscular passageway connecting the cervix with the external genital organs), the cervix (the lower part of the uterus which separates the body of the uterus from the vagina), the uterus (a hollow, muscular structure), the ovaries (the glands which produce the eggs and oestrogen), and fallopian tubes (two muscular channels that connect the ovaries with the uterus).

Male Reproductive System

Unlike its female counterpart, whose sex organs are inside the body, the male reproductive system includes sex organs, or genitals, that are situated both inside and outside the body. These are the testicles; duct system, including the epididymis and vas deferens; accessory glands; and penis.