The Checklist

The female body

Ovary: there are 2 ovaries, each about the size of an almond, which produce the eggs, or ova

Womb, or Uterus: about the size and shape of a small, upside-down pear. It is made of muscle and expands when a baby grows inside it

Fallopian tube: 2 tubes leading from the ovaries to the womb

Bladder: sac of muscular, fibrous tissue holding urine

Urethra: tube which carries urine from the bladder

Vagina: opening extending approximately 8 centimetres long from the cervix to the vulva, where it opens between the legs

Anus: opening at the lower end of the bowel which is kept closed by 2 muscles

Cervix: the neck of the womb. It is normally all but closed, with just a small opening through which blood passes during menstruation

Clitoris: sensitive organ at the top of the female genitals, only the tip is visible. During sexual excitement, the clitoris enlarges and hardens and can be the focus of orgasm

Penis: organ made up of spongy tissue which when aroused, fills with blood making it stiff and hard. The average length of the penis is around 12 to 19 centimetres when erect

Urethra: tube which carries urine from the bladder, and semen (including sperm) through the penis

Glans: helmet-shaped head of the penis

Foreskin: skin that covers the glans and must be pulled back for cleaning to avoid infection

Sperm: tiny tadpole-shaped cells, which when joined with an egg cell from a woman, fertilise and form a new cell

Semen: the liquid in which the sperm swim. Sperm are needed to fertilise an egg in the woman to make a baby. During ejaculation urine cannot enter the sperm. On average, one teaspoonful of semen contains up to 300 million sperm

Scrotum: bag containing the testicles underneath the penis

Testicles: soft round organs that produce sperm