Puberty happens because of certain hormones and genes in the body. Although the reason why puberty starts early for some people and starts late for others is still not known, some factors are thought to be responsible for it.
Research has shown that puberty starts because of a gene called KiSS1. Another gene named GPR54 remains in disabled state in the body for many years before being set into motion by the chemical kisspeptins. Kisspeptins is produced by the KiSS1 gene. GRP54 gene sends signals to the brain upon which a chain reaction takes place and the puberty process starts.
The hypothalamus portion of the brain sends signals some signals to the pituitary gland (this is a small gland located at the base of the brain), this causes the gland to secrete some hormones which helps create sex hormones in the ovaries of girls and testicles of boys.
The changes during puberty take place because of this chain reaction and the release of these hormones.
Two hormones are produced in the ovaries and testicles which cause the changes to happen during puberty. These two hormones are:
- Testosterone produced in the testicles: The effect of this on a boy’s body is accelerated growth of the penis and testicles, increased muscles and more hair around the genitals. It also causes the voice to change.
- A small amount of testosterone is also produced in the bodies of girls and women by the ovaries, it helps keep their muscles and bones healthy.
- Estrogen produced in the ovaries: In girls this has the effect of forming breasts and the female reproductive system and their menstrual cycle is controlled by this hormone.
- Boys and men also have some amounts of estrogen in their bodies; it is produced in their brain and testicles. It helps to maintain their bone density.
Triggers of Puberty:
Some environmental and genetic control factors are thought to influence the beginning of puberty. Research has shown that puberty starts earlier in black girls than in white girls. However no proof has been found which shows that black boys grow up faster than white boys. In the case of girls the matters of nutrition and food habits are also thought to be especially important. Studies have shown that puberty starts comparatively earlier in girls who have higher than normal weight than girls who have lower than normal weight.
The recent trend of girls having higher than normal weight might have a relation with the decrease in the average age at which puberty starts for girls. However it is not yet known why increased weight has no effect on boys.
Not much is known for sure about why certain factors have an effect on puberty. Research is going on in this subject. Find out different information about why puberty starts early or late.
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