Write a short note on estrogens?

Hint: Estrogen is a female sex hormone. It is a steroid hormone. Estrogen is also present in males but its level is comparatively lower than in females.

Complete Answer:
Estrogen in females is responsible for the development of female reproductive system and secondary sex characters after puberty.
Secondary sexual characters are the characters that distinguish a girl from a boy. These characters in females are –
- Growth of the breast
- Start of menstrual cycle
- Hip region become wider
- Estrogen is synthesized in all vertebrates and also in a few birds.
- Estrogen can readily diffuse across the cell membrane.
- In females, the main source of estrogen production are ovaries but it can also be secreted by the adrenal gland in small amounts.

There are 4 types of estrogen:
1. Estrogen (E1) – Estrogen is predominant circulatory estrogen at the time of menopause (time when menstrual period stops).
2. Estradiol (E2) – Estradiol is a predominant estrogen during reproductive years.
3. Estriol (E3) – It is the predominating circulatory estrogen in terms of serum levels.
4. Estetrol (E4) – It is another type of estrogen. This type of estrogen is produced only at the time of pregnancy.

Note: Estrogen in addition works as a natural hormone, it can also be used for medication purposes. For example – in menopause hormone therapy, hormonal birth control, etc. Estrogen has other functions like it keeps cholesterol in control, protects bone health for both women and men, etc.