AP 8th Class Biology Notes Chapter 5 Reaching the Age of Adolescence
→ Balanced Diet : The meals that contains proteins, carbohydrates, fats and vitamins in requisite proportions.
→ Endocrine Glands : These are also called ductless glands. They help in the regulation of functioning of human body. They release hormones.
→ Estrogen : It is a female hormone produced by ovaries.
→ Hormones : These are the chemical substances produced by endocrine glands. Ex: Thyroxine.
→ Insulin : It is a hormone secreted by pancreas. It regulates the sugar levels in blood. Insufficient production of insulin causes diabetes.
→ Larynx : It is a part of human respiratory system and also known as voice box. It has voice cords which vibrate during expiration and producing sounds.
→ Pituitary Gland : It is the master gland of endocrine system. It secretes hormones which include growth hormone and hormones that make other glands to secrete hormones.
→ Puberty : The age in which human body undergoes several changes the boys and girls show their capability to reproduce.
→ Reproductive Health : Personal health and hygiene of adolescents must be given proper care and attention. Girls should take special care of cleanliness during menstruation.
→ Secondary Sexual Characters : The features that help to distinguish the male from female are called secondary sexual characters.
→ Sex Chromosomes : The chromosomes which determine the sex of the baby are called sex chromosomes. One pair of sex chromosomes are present in humanbeings. They are called allosomes.
→ Target Site : Endocrine glands release hormones into the blood stream to reach a particular body part is called target site.
→ Testosterone : This is the male sex hormone released by the testes at the onset of puberty.
→ Thyroxine : Thyroid gland secretes a hormone called thyroxine. The metamorphosis in frog is regulated by thyroxine.
→ Voice Box : It is also called larynx. It is the voice producing part of throat is called Voice box.
→ Growing up is a natural process. The period of life when the body undergoes changes leading to reproductive maturity is called adolescence.
→ The human body undergoes several changes during adolescence. These changes mark the onset of puberty.
→ Puberty is that; boys and girls become capable of reproduction. Puberty ends when adolescent reaches reproductive maturity.
→ The on set of puberty brings about growth of the reproductive organs. Hair grow at various places on body. Breasts develop in girl and facial hair (moustache and beard) appear in boys. Voice of boys becomes hoarse as voice box enlarges during adolescence.
→ Adam’s apple is actually a partial growth of Voice box.
→ The most conspicuous change during puberty is the sudden increase in height.
→ The on set of puberty and maturity of reproductive organs are controlled by hormones.
→ Hormones are secretions of endocrine glands which release them directly into blood stream.
→ Pituitary gland secretes hormones which include growth hormone and hormones that make other glands such as testes, ovaries, thyroids and adrenals, secrete hormones.
→ Pancreas secretes insulin; thyroid produces thyroxine and adrenals produces adrenalin.
→ Testosterone is the male hormone and estrogen the female hormone.
→ The matured testes start producing sperm cells. The matured ovaries begin to release ova for every 28 to 30 days is called menstrual cycle.
→ The first menstrual cycle begins at adolescence and is termed as “menarche” stoppage of menstruation at the age of 45-50 is called “menopause”.
→ Sex of the unborn child depends upon whether the zygote has XX or XY chromosomes.
→ It is important to eat balanced food and maintain personal hygiene during adolescence.
→ Child marriage is a social evil.
→ The legal age for marriage is 18 years for girls and 21 years for boys.
→ Adolescence is a period of stress and strain. So, it is more essential to be careful about health and hygiene.