Chapter 10 reaching the age of
adolescence
Define terms
1)-Adolescence- The transition state
between childhood and adulthood is
called adolescence the period of life when
the body undergoes changes leading to to
reproductive maturity
2).Adrenaline hormone-The hormone
that prepares the body to fight and run
fast
3).Balanced diet- A diet with all food
nutrients at required proportion is called a
balanced diet.
4).Endocrine glands- The ductless
gland which secretes the chemicalsor
regulators that is hormone to control
physical growth metabolism and other
changes that occur in the body during
adolescence number
5).Estrogen- The female hormone
produced in ovary is called estrogen.
6) Hormones-Chemical regulators
released by endocrine glands are called
hormones.
6) Hormones- Chemical regulators
released by endocrine glands are called
hormones.
7).Insulin- Hormone secreted by
pancreas that regulates sugar
metabolism is called insulin
8 ).Larynx- The area at the top of the
throat that contains the muscle which
which moves to produce voice larynx is
called voice box
9)-Pituitary gland- The master gland that
controls the function of other glands
10).Puberty the state of changes from
childhood to adulthood.
11).Reproductive health- Reproductive
health is the state of male and female
reproductive system during all life stages
these systems are paid up of organs and
hormone producing glands.
8:45am
EXercises
Question 1:
What is the term used for secretions of endocrine glands responsible for changes taking place in the
body?
Answer 1:
Hormones are chemical messengers that transport signal from one cell (or gland) to another cell (or
gland).
Question 2:
Define adolescence.
Answer 2:
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.
Question 3:
What is menstruation? Explain.
Answer 3:
In a female reproductive ovaries, the ova begin to mature with the onset of puberty. One ovum
matures and released by one of the ovaries once in about 28 to 30 days. During this period, the wall
of the uterus becomes thick so as to receive the egg, in case it is fertilized and begins to develop. If
fertilization does not occur, the released egg and the thickened lining of the uterus along with its
blood vessels are shed off. This causes bleeding in female which is called menstruation. Menstruation
Occurs once in about 28 to 30 days.
Question 4:
List changes in the body that take place at puberty.
Answer 4:
DR
Common changes occur among boys and girls during puberty:
Suddenincrease in height.
Change in body shape.
Change in voice. In boys voice becomes deep and harsh, in girls it is high pitched voice.
Increased activity of sweat and sebaceous glands.
Reproductive organs begin to mature.
Appearance ofsecondary sexual characteristics.
Changes in Boys during puberty:
Facial hairs such as beard and moustaches develop.
Hair develops under the armpit, under chest and in the pubic regions.
Voice becomes deeper.
Muscles develop, and shoulder becomes broad.
Increase in weight.
Changes in Girls during puberty:
Developmentand enlargement of breasts.
Hair develops under the armpit and in the pubic regions.
Hips broaden and pelvic region widens.
Initiation of menstrual cycle.
Deposition of fat around hips.
(Class- 8)
Question 5:
Prepare a Table having two columns depicting names of endocrine glands and hormones secreted by
them.
Answer5:
S. No. Endocrine Gland Hormone Secreted
1 Pituitary Growth Hormones
Thyroid Thyroxine
Adrenal Adrenalin
Pancreas Insulin
5. Testes Testosterone
6. Ovaries
Oestrogen& Progesterone
Question 6:
What are sex hormones? Why are they named so? State their function.
Answer 6:
Hormones which constitute the secondary sexual characters are called sex hormones. In
general,
hormones work instantly when they released in blood stream. Sex hormones are different because
they start to work later on. They gradually
prepare in the for
body
The sex hormones are responsible for the fundamental reproduction.
change in growth & development and
stimulate the developments of
secondary sexual characters. The testes and the ovaries are the
reproductive Organs and both are stimulated by the pituitary hormone during Puberty. That's the
reason these are called sex hormones.
Functions of Sex Hormones:
I n male, the testes produces the male sex hormone testosterone. This hormone helps in the
development and maintenance of the primary and secondary sexual characters and
production of sperms.
I n female, the ovaries secrete oestrogen and progesterone responsible for the primary and
secondary sexual characters.
Question 7:
Choose the correct option.
(a) Adolescents should be careful about what they eat, because
0 proper diet develops their brains.
(i) proper diet is needed for the rapid growth taking place in their body.
(iii) adolescents feel hungry all the time.
(iv) taste buds are well developed in teenagers.
(b) Reproductive age in women starts when their
0 menstruation starts.
(ii) breasts start developing
i) body weight increases.
(iv) height increases.
(c) The right meal for adolescents consists of
() chips, noodles, coke.
Ci) chapati, dal, vegetables.
ii) rice, noodles and burger.
(iv) vegetable cutlets, chips and lemon drink.
(Cass
Answer 7:
(a) Adolescents should be careful about what they eat, because (1) proper diet is needed for the rapid
growth taking place in their body.
(b) Reproductive age in women starts when their () menstruation starts.
(c)The right meal for adolescents consists of(il) chapati, dal, vegetables
Question 8:
Write notes on-
(a) Adam's apple.
(b) Secondary sexual characters.
(c) Sex determination in the unborn baby.
Answer 8:
(a) Adam's apple: The protruding part of the throat is called Adam's apple. It is the enlarged voice
box or larynx which gets enlarged and visible from outside in boys at the onset of puberty. This makes
the voice of boys hoarse.
(b) Secondary sexual characters: Secondary Sexual Characters are those characters which distinguish
a male from female. Some of the characters are as follows:
Boys
Facial hairs such as beard and moustaches develop.
Hair develops under the armpit, under chest and in the pubic regions.
>Voice becomes deeper.
Muscles develop, and shoulder becomes broad.
>Increase in weight.
Girls:
IWARI
Development and enlargement of breasts.
Hair develops under the armpit and in the pubic regions.
Hips broaden and pelvic region widens.
Initiation of menstrual cycle.
Deposition offat around hips.
(c) Sex determination in the unborn baby: All human beings have 23 pairs of chromosomes in the
nuclei of their cells. Out of these two chromosomes are the sex chromosomes, named X and Y. A
female has two X chromosomes, while a male has one X and one Y chromosome. The gametes (egg
and sperm) have only one set of chromosomes. The unfertilised egg always has one X chromosome
but sperms may have X or Y. When a sperm containing X chromosome fertilises the egg, the zygote
would have two X chromosomes and develop into a female child. If the sperm contributes a Y
chromosome to the egg (ovum) at fertilisation, the zygote would develop into a male child. This
concludes that the sex chromosomes of the father determine the sex of an unborn baby.
Question 9:
Word game: Use the clues to work out the words.
Across
3. Protruding voice box in boys
4. Glands without ductss
7. Endocrine gland attached to brain
8. Secretion of endocrine glands
9. Pancreatic hormone
10. Female hormone
Down
1. Male hormone
2. Secretes thyroxine
3. Another term for teenage
5. Hormone reaches here through blood
stream
6. Voice box
7. Term for changes at adolescence
LAnswer 9
DA MSEPPEE
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