Chapter 17
Breathing and Exchange of Gases
1. Draw the diagram of a sarcomere of skeletal muscle showing different regions.
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2. Define sliding filament theory of muscle contraction.
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3. Describe the important steps in muscle contraction.
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4. Write true or false. If false change the statement so that it is true.
(a) Actin is present in thin filament
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(b) H-zone of striated muscle fibre represents both thick and thin filaments.
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(c) Human skeleton has 206 bones.
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(d) There are 11 pairs of ribs in man.
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(e) Sternum is present on the ventral side of the body.
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5. Write the difference between :
(a) Actin and Myosin
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(b) Red and White muscles
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(c) Pectoral and Pelvic girdle
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6. Match Column I with Column II :
Column I Column II
(a) Smooth muscle (i) Myoglobin
(b) Tropomyosin (ii) Thin filament
(c) Red muscle (iii) Sutures
(d) Skull (iv) Involuntary
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7. What are the different types of movements exhibited by the cells of human body?
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8. How do you distinguish between a skeletal muscle and a cardiac muscle?
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9. Name the type of joint between the following:-
(a) atlas/axis
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(b) carpal/metacarpal of thumb
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(c) between phalanges
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(d) femur/acetabulum
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(e) between cranial bones
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(f) between pubic bones in the pelvic girdle
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10. Fill in the blank spaces:
(a) All mammals (except a few) have __________ cervical vertebra.
(b) The number of phalanges in each limb of human is __________
(c) Thin filament of myofibril contains 2 ‘F’ actins and two other proteins namely
__________ and __________.
(d) In a muscle fibre Ca++ is stored in __________
(e) __________ and __________ pairs of ribs are called floating ribs.
(f) The human cranium is made of __________ bones
Type Susmita Kakati
