What are secondary sexual characteristics?
Physical features associated with sexual maturity that are not the reproductive organs themselves.
Cambridge IGCSE (9–1) Biology 0970 (Extended) (2026–2028) · 16.5
Revise Cambridge IGCSE (9–1) Biology 0970 (Extended) (2026–2028) specification point 16.5, Sex hormones in humans, with free active-recall flashcards. Flip through the set or review every question and answer below.
1 / 27
What are secondary sexual characteristics?
Physical features associated with sexual maturity that are not the reproductive organs themselves.
What stimulates the development of secondary sexual characteristics during puberty?
Increased production of sex hormones.
Where is testosterone mainly produced?
In the testes.
What are three changes promoted by testosterone during puberty?
Where is oestrogen mainly produced?
In the ovaries.
What are two changes promoted by oestrogen during puberty?
What role do sex hormones play in secondary sexual characteristics once they have developed?
They help maintain those characteristics.
What is the menstrual cycle?
A recurring sequence of linked changes in the ovaries and uterine lining.
What happens to an egg in the ovary during the menstrual cycle?
It matures and is released at ovulation.
How does the uterine lining change after menstruation?
It rebuilds and thickens, preparing for a possible pregnancy.
What happens to the uterine lining if pregnancy does not occur?
It breaks down and is shed during menstruation, and a new cycle begins.
Which gland releases FSH and LH?
The pituitary gland.
What does FSH stimulate in the ovary?
The development of an ovarian follicle.
Which ovarian structure produces oestrogen as it develops?
The developing follicle.
What effect does oestrogen have on the uterine lining?
It stimulates the lining to rebuild and thicken.
What hormonal change helps trigger the LH surge?
A rise in oestrogen.
What triggers ovulation?
A surge of LH.
What does LH promote the emptied follicle to become?
The corpus luteum.
Which hormone does the corpus luteum produce?
Progesterone.
What effect does progesterone have on the uterine lining?
It maintains the thickened lining.
How do oestrogen and progesterone limit the development and release of further eggs during a menstrual cycle?
They inhibit FSH and LH release.
What sequence leads to menstruation if pregnancy does not occur?
How does the main site of progesterone and oestrogen production change during pregnancy?
The corpus luteum in the ovary produces both hormones early in pregnancy; the placenta later becomes the main production site.
What is progesterone’s role in maintaining pregnancy?
It maintains the thickened uterine lining, preventing it from being shed.
What is oestrogen’s role in maintaining pregnancy?
It supports the maintenance of the uterus during pregnancy.
Which two hormones have their release inhibited by sustained progesterone and oestrogen levels during pregnancy?
FSH and LH.
What effect does inhibition of FSH and LH have on ovarian activity during pregnancy?
It prevents another ovarian follicle from developing and ovulating while pregnancy continues.