The male reproductive system

Draw the testes (two oval organs inside the scrotum): these produce sperm and the hormone testosterone. The sperm duct (vas deferens) carries sperm from each testis to the urethra. The prostate gland and seminal vesicles add fluid to the sperm to form semen. The penis delivers semen into the female reproductive system during sexual intercourse. The urethra is shared between the reproductive and urinary systems.

The female reproductive system

Draw the two ovaries: these produce eggs (ova) and the hormones oestrogen and progesterone. The oviducts (Fallopian tubes) connect the ovaries to the uterus. Each oviduct has a funnel-shaped end near the ovary to collect the released egg. The uterus has a thick muscular wall and a lining (endometrium) where the embryo implants. The cervix is the narrow opening at the base of the uterus leading to the vagina.

Where fertilisation and development occur

Fertilisation occurs in the oviduct: not in the uterus. A sperm cell fuses with an egg cell to form a zygote. The zygote divides as it travels along the oviduct and implants in the uterus wall as an embryo. During pregnancy, the placenta develops, providing the embryo with oxygen and nutrients from the mother's blood and removing carbon dioxide and urea.