Students should be able to describe the roles of hormones in human…

The idea

Reproduction in humans is controlled by hormones. FSH, released by the pituitary gland, causes an egg to mature in an ovary and stimulates the ovaries to release oestrogen. Oestrogen, produced by the ovaries, causes the lining of the uterus to thicken and stimulates the release of LH. A surge of LH from the pituitary gland triggers ovulation, the release of a mature egg from the ovary. After ovulation, the remains of the follicle form the corpus luteum, which secretes progesterone. Progesterone maintains the lining of the uterus, ready for a fertilised egg to implant. If fertilisation does not occur, the corpus luteum breaks down, progesterone levels fall, and the lining is shed as menstruation. The cycle then begins again.

What earns the marks

• FSH is released by the pituitary gland and causes an egg to mature in the ovary.
• Oestrogen is produced by the ovaries and causes the lining of the uterus to thicken.
• LH is released by the pituitary gland and triggers ovulation.
• Progesterone is produced by the corpus luteum and maintains the lining of the uterus.
• If fertilisation does not occur, progesterone levels fall and the lining of the uterus is shed during menstruation.
• The hormones interact through feedback, so changes in one hormone affect the release of others.

Common mistakes and how to put them right

• Confusing FSH and LH.

  Put it right: FSH matures the egg, while LH triggers ovulation.

• Saying that oestrogen maintains the uterus lining.

  Put it right: Progesterone maintains it, while oestrogen thickens it.

• Thinking that progesterone is always high.

  Put it right: It falls when the corpus luteum breaks down, causing menstruation.

Exam tips

• Name the gland or organ that releases each hormone when describing its role.
• Sequence the events of the menstrual cycle in order, linking each hormone to its effect.
• Use the terms ovulation, corpus luteum and menstruation accurately in written answers.