Adolescents should be careful about what they eat, because

1

(a)

proper diet develops their brains.

(b)

proper diet is needed for the rapid growth taking place in their body.

(c)

adolescents feel hungry all the time.

(d)

taste buds are well developed in teenagers.

The release of an egg from an ovary is called

1

(a)

fertilisation

(b)

menopause

(c)

menstruation

(d)

ovulation

For the metamorphosis of tadpoles which of the following elements must be available in water?

1

(a)

Chlorine

(b)

Carbon

(c)

Sulphur

(d)

Iodine

Protruding part of the throat in a boy is called

1

(a)

Voice box

(b)

Larynx

(c)

Adam's Apple

(d)

All of these

Sex chromosomes in a female body are

1

(a)

X

(b)

Y

(c)

XX

(d)

XY

Metamorphosis in amphibians such as frog is brought about by ______________ hormone

1

(a)

thyroxine

After attaining puberty, boyc develop a _____________ voice.

1

(a)

deep

_____is male hormone and_______ is the female hormone.

1

(a)

Testosterone, estrogen

Testes are responsible for production of sperms.

1

(a) False

(b) True

Half the female gametes contain X-chromosomes and the other half contain Y -chromosomes.

1

(a) True

(b) False

The menstrual flow lasts for 28-30 days.

1

(a) True

(b) False

Adolescence is a stage of slow growth and development

1

(a) True

(b) False

The first menstruation flow is termed as menopause

1

(a) True

(b) False

Unscramble the underlined words in the following sentences
Reproductive life of a woman lasts from hacreemn to spauoemen.

1

(a)

menarche, menopause,

What is puberty?

1

(a)

The human body undergoes several changes during adolescence.Thesechangesmark the onset of puberty

Why should we say 'No' to Drugs?

1

(a)

They ruin health and happiness both

Name the hormone which controls metamorphosis in frog

1

(a)

Thyroxine hormone which is produced by thyroid controls the metamorphosis in frog

What happens if there is no iodine present in water?

3

(a)

If there is no iodine present in water, the tadpole cannot become adult

What is the term used for chemical secretions of endocrine glands responsible for changes taking place in the body?

3

(a)

List changes in the body that take place at puberty.

3

(a)

Fill the blank circles in figure and identify the sex of child A and B.

3

(a)

Humans attain sexual maturity during puberty. How does this happen? Explain

3

(a)

Why is pituitary gland called 'Master Gland'?

3

(a)

Observe the chart and graph given in figure carefully and answer the following questions.

Age in years	% of full height
	Boy	Girl
8	72%	77%
9	75%	81%
10	78%	84%
11	81%	88%
12	84%	91%
13	88%	95%
14	92%	98%
15	95%	99%
16	98%	99.5%
17	99%	100%
18	100%	100%

(a) Which of the line represents the height of boys?
(b) Which line represents the height of girls?
(c) What is the difference between the pattern of increase in the height of boys and girls?
(d) Is this pattern true for each individual?

5

(a)

In figure, mark the position of the endocrine glands which release the hormones that
(a) control the release of sex hormones.
(b) are responsible for the secondary sexual characters in boys.
(c) prevent diabetes.
(d) maintain the correct salt balance in the blood.

5

(a)