Reaching the Age of Adolescence
Between the ages of 11 and 19 years, children are called adolescents.
Adolescents are also called ‘teenagers’.
Humans become capable of reproduction after the onset of puberty.
Changes that occur at puberty are:
In females, maturation and release of ova start from the age of 10-12 years.
Menstrual flow commences at puberty, which is called menarche.
It stops at the age of 45-50, which is called menopause.
When the state of well being is with special reference to reproductive conditions, it is reproductive health.
To maintain this, human beings need follow a balanced diet.
Maintenance of personal hygiene and exercise is also very important.
Drug abuse is the unfortunate addiction in teenagers towards hard drugs like morphine and cocaine.
This happens due to unhappiness, dissatisfaction, depression, anxiety and boredom in teenagers.
Drugs are addictive and they harm the body in the long run. So, they should be avoided.
Human beings contain 23 pairs of chromosomes, in which X and Y are the sex chromosomes.
Males have two distinct sex chromosomes (X and Y).
Whereas, females have both X chromosomes.
When a sperm containing X chromosome fertilises the egg, female offspring is produced.
Whereas, when a sperm containing Y chromosome fertilises the egg, male offspring is produced.
- Change in height and body shape
- Change in voice due to growing voice box, which can be seen as Adam’s apple in boys and high pitched voice in girls
- Increased activity of sweat and sebaceous glands
- Development of sex organs
- Development of mental, intellectual and emotional maturity
- Development of secondary sexual characteristics
- Release of sex hormones
The 22 pairs of chromosomes other than the sex chromosomes are known as the Autosomes.
Hormone is a chemical substance secreted in one part of an organism and transported to another part of that organism (target site) where it has a specific effect.
Thyroid, pancreas and adrenal glands are the endocrine glands in the body.
These are ductless glands which secrete their hormones directly into the bloodstream.
Exocrine glands secrete their products into ducts.
Thyroid gland releases the hormone thyroxin.
Absence of thyroxin in the body causes goitre.
In insects, metamorphosis is controlled by insect hormones. While in frog, it is controlled by thyroxine.
Pancreas is responsible for the secretion of Insulin, and in the absence of insulin, a person become diabetic.
Adrenaline is released from the adrenal gland which helps the body to adjust with conditions of stress.
Growth hormones are secreted from the pituitary gland.
Pituitary gland is secretes testosterone in males and estrogen in females.