Q1. What is adolescence?
Ans. It is the period of life when the body undergoes changes, leading to reproductive maturity.
Q2. Define puberty.
Ans. The stage when human body becomes sexually mature.
Q3. What is adam’s apple?
Q3. What is adam’s apple?
Ans. The growing voice box in boys can be seen as a protruding part of the throat called adam’s apple.
Q4. What are secondary sexual characters?
Ans.These are the features that help to distinguish males from females.
Q5. Define the following terms.
Ans. (a) Hormone- they are chemical messengers for various processes and activities in the body
(b) Endocrine glands- the ductless glands which secrete hormones directly into blood.
Q6. Enlist the changes occurring in males and females during puberty.
Ans.
Type of change
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In girls
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In boys
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Increase in height
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Sudden increase
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Sudden in crease
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Body shape
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Waist widens
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Shoulders broadens
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Voice change
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High pitched
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Voice becomes deeper
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Development of sex organs
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Ovaries mature and releaseseggs.
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Testes matures and produces sperms
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Q7. What is the role of hormones in initiating reproductive function?
Ans.1. Hormones from pituitary stimulate testes and ovaries to release testosterone and estrogen respectively.
3. These sex hormones reach to target sites via blood.
4. Then stimulate changes in the body at the onset of puberty.
Q8. Discuss reproductive phase of life in women.
Ans. In females the reproductive phase of life begins at puberty and continues till they reach the age of 45-50 years. The egg begins to mature with the onset of puberty. One mature ovum is released by one of the ovaries every month. The process is called ovulation. During this period, the walls of the uterus become thick so as to receive fertilized egg. Then this egg gets implanted in the uterus resulting in pregnancy.
Q9 Give reasons for the following :
a. Tadpoles growing in iodine deficient water have retarded growth.
Ans. The process of growth and development is regulated by thyroxine hormone which is produced by thyroid gland. Iodine is required for thyroxine production. That is why retarded growth is seen in tadpoles living in iodine deficient water.
b. Voice becomes hoarse in adolescent boys.
Ans. Sometimes the muscles of the growing voice box go out of control and the voice becomes hoarse.
c. Adolescents experience acne and pimples.
Ans. This is dues to increased activity of sebaceous (oil) glands in the skin.
d. Females have no role in determining gender of a child.
Ans. Y- chromosomes that leads to a boy offspring is contributed by male parent. That is thesperms are of two types, having either X or Y chromosome.
10. What are the causes of AIDS?
Ans. The causes of AIDS are:
1. Sharing needle of the syringe
2. unprotected sex with infected person.
3. blood transfusion from infected person to healthy one.
4. infected mother can pass HIV through milk to an infant.
8th Chapter: Reaching the Age of Adolescence
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[Study Notes] by Educational service
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CBSE Solved Questions Paper-1
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CBSE Solved Questions Paper-2
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CBSE Solved Questions Paper- 3
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CBSE Solved Questions Paper- 4
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VIII Reproduction in Animals
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Reproduction in Animals [E-NOTES]
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CBSE Test Paper [solved question]
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CBSE Worksheet for practice
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Reproduction & Endocrine [solved]
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