Reproductive hormones
A hormoneChemical messenger produced in glands and carried by the blood to specific organs in the body. is a chemical substance produced by a glandAn organ or tissue that makes a substance for release, such as a hormone.. Hormones are carried by the blood around the body but alter the activity of specific target organThe organ with receptor molecules on its cell surfaces which recognise a specific hormone. only.
Different hormones affect different organs or cells.
Puberty
pubertyTime during which sexual maturity happens. is the stage in life when a child's body develops into an adult's body. The changes take place gradually, usually between the ages of 10 and 16.
During puberty, reproductive hormones cause secondary sex characteristics to develop:
- testosteroneMale sex hormone produced in the testes, which is responsible for puberty in boys. - produced by the testes - is the main male reproductive hormone and it stimulates sperm production.
- oestrogenA female sex hormone produced in the ovaries, which is responsible for puberty in girls and the regulation of the menstrual cycle. - produced by the ovaries - is the main female reproductive hormone. At puberty, eggs begin to mature and one is released approximately every 28 days. This is called ovulation.
Changes during puberty
A variety of changes happen to boys and girls during puberty.
Boys only | Boys and girls | Girls only |
Voice breaks | Pubic hair grows | Voice deepens gradually |
Hair grows on face and body | Underarm hair grows | Hips get wider |
Body becomes more muscular | Sexual organs grow and develop | Breasts develop |
Testes start to produce sperm cells | Ovaries start to release egg cells - menstruation starts |
Boys only | Voice breaks |
---|---|
Boys and girls | Pubic hair grows |
Girls only | Voice deepens gradually |
Boys only | Hair grows on face and body |
---|---|
Boys and girls | Underarm hair grows |
Girls only | Hips get wider |
Boys only | Body becomes more muscular |
---|---|
Boys and girls | Sexual organs grow and develop |
Girls only | Breasts develop |
Boys only | Testes start to produce sperm cells |
---|---|
Boys and girls | |
Girls only | Ovaries start to release egg cells - menstruation starts |
Learn more about hormones and the menstrual cycle with Dr Alex Lathbridge.
Listen to the full series on 大象传媒 Sounds.