Ans. Girls should take special care of cleanliness during the time of menstrual flow. They should keep track of their menstrual cycle and be prepared for the onset of menstruation.
Ans. Drugs should be avoided because they are addictive. If we take them once, we feel like taking them again and again. They harm the body in the long run. They ruin health and happiness.
Ans. The bigger voice box in boys gives deeper voice or low pitched voice to the boys. In adolescent boys, sometimes, the muscles of the growing voice box go out of control and the voice becomes hoarse.
Ans. Menstruation occurs once in about 28 to 30 days. The first menstrual flow begins at puberty and is termed menarche. At 45 to 50 years of age, the menstrual cycle stops. Stoppage of menstruation is termed menopause.
Ans. During puberty the secretion of sweat glands and sebaceous glands (oil glands) increases. Many young people get acne and pimples on the face at this time because of the increased activity of these glands in the skin.
Ans. Hormones are chemical substances. These are secretions from endocrine glands, or endocrine system. They are responsible for changes taking place in the body.
Ans. It is necessary for teenagers because the increased activity of sweat glands sometimes makes the body smelly. All parts of the body should be washed and cleaned every day. If cleanliness is not maintained there are chances of catching bacterial infection.
Ans. Early marriage and motherhood cause health problems in the mother and the child. It also curtails employment opportunities for the young woman and may cause mental agony as she is not ready for responsibilities of motherhood.
Ans. In a frog, metamorphosis is controlled by thyroxine, the hormone produced by thyroid. Thyroxine production requires the presence of iodine in water. If the water in which the tadpoles are growing does not contain sufficient iodine, the tadpoles cannot become adults.
Ans. The period of life, when the body undergoes changes, leading to reproductive maturity, is called adolescence. Adolescence begins around the age of 11 and lasts upto 18 or 19 years of age. In girls, adolescence may begin a year or two earlier than in boys. Also, the period of adolescence varies from person to person.
Ans. AIDS which is caused by a dangerous virus, HIV. This virus can pass on to a normal person from an infected person by sharing the syringes used for injecting drugs. It can also be transmitted to an infant from the infected mother through her milk. The virus can also be transmitted through sexual contact with a person infected with HIV.
Ans. Height of an individual is more or less similar to that of some family member. This is because height depends on the genes inherited from parents. It is, however, very important to eat the right kind of food during these growing years. This helps the bones, muscles and other parts of the body get adequate nourishment for growth.
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