TIME: – 1.5HR F.M.:- 50

Reaching the age of Adolescence
Reproduction in Animals
Synthetic Fibres and Plastics.

Q1. Each question carries 1mark.

(i) What are exocrine glands?
(ii) Growth hormone is secreted by ________________ gland.
(iii) Which kind of capability does frog gain by transforming from tadpole to adult frog?
(iv) Give examples of some oviparous and viviparous animals.
(v) Cellulose is made up of large number of___________________ units.

Q2. Each question carries 2marks.

(i) What is the relation between adolescence and puberty?
(ii) Define secondary sexual characters.
(iii) Differentiate between zygote and foetus.
(iv) Why we prefer plastic containers for storage of items like water, milk, pickles, dry food? (v) Differentiate between natural and artificial fibres.

Q3. Each question carries 3marks.

(i) What is the cause of
A. Diabetes     B. Goitre        C. AIDS
(ii) Write short notes on
A. increase in height during puberty.
B. changes in body shape during puberty.
C. voice change at puberty.
(iii) Why frog lays egg coverless, whereas, Hen lays it with hard cover? Explain.
(iv) What are the advantages of artificial silk over natural silk? (v) State the source of following fibres
A. Cotton B. Rayon C. Nylon

Q4. Each question carries 5marks.

(i) A. Explain the process of sexual reproduction in human beings.
B. Name different stages of the lifecycle of a frog and silkworm.
(ii) Draw labeled diagram of male and female reproduction system.
(iii) What are synthetic fibres and its various types?
(iv) Explain secondary sexual characters and roles of hormones in initiating reproductive function.

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