This weeks biology virtual period is on Sex hormones and puberty.
2. The female hormones responsible for the development of the secondary sexual characteristics are; oestrogen and progesterone. The male hormone responsible for the development of the secondary sexual characteristics is testosterone. These hormones are stimulated by Luteinising Hormone (LH) and Follicle Stimulating Hormone (FSH) .
- FSH: It is produced by the pituitary gland and it:
- Causes an egg to mature in an ovary.
- Stimulates the ovaries to release the hormone oestrogen.
- LH: It causes the mature egg to be released from the ovary.
- Oestrogen: It is secreted by the ovaries and it:
- Stops FSH being produced – so that only one egg matures in a cycle.
- Stimulates the pituitary gland to release the hormone LH.
- Progesterone: It is secreted by ovaries. It maintains the lining of the uterus during the middle part of the menstrual cycle and during pregnancy.
- Oxytocin: It is a hormone produced by the hypothalamus and secreted by the pituitary gland. This important hormone plays a crucial role in the childbirth process and also helps with male reproduction.
- HCG: It is a hormone produced by the placenta after implantation. Human chorionic gonadotropin interacts with the LHCG receptor of the ovary and promotes the maintenance of the corpus luteum during the beginning of pregnancy.
- Prolactin: It is a hormone produced by the pituitary gland, named because of its role in lactation. It also has other wide-ranging functions in the body, from acting on the reproductive system to influencing behaviour and regulating the immune system.
- Testosterone: It is a hormone that is responsible for many of the physical characteristics specific to adult males. It plays a key role in reproduction and the maintenance of bone and muscle strength.
a. When they are 12 years old.
c. The growth of pubic hair on girls and the first menstrual period.
d. No, it’s not the most common, but it is normal.