OCR General Certificate of Secondary Education (GCSE) Biology Practice Exam

Where is oestrogen produced in the body?

1. In the adrenal glands

2. In the testes

3. In the ovaries

4. In the thyroid gland

The correct answer is: In the ovaries

Oestrogen is primarily produced in the ovaries, which are the female reproductive organs responsible for the production of eggs and hormones. During various stages of a woman's menstrual cycle, specific cells in the ovaries, known as ovarian follicles, secrete oestrogen. This hormone plays a crucial role in regulating the menstrual cycle, promoting the development of secondary sexual characteristics, and maintaining reproductive functions. While other glands do produce hormones, they do not primarily produce oestrogen. For example, the adrenal glands primarily produce adrenaline and cortisol, and while they do produce a small amount of oestrogen, it is not their primary function. The testes are responsible for producing testosterone, and the thyroid gland primarily regulates metabolism through hormones like thyroxine. In contrast, the ovaries are specifically designed for the production of oestrogen, making this option the correct one.