Match each item in Column I with one item in Column II and chose your answer from the codes given below:
Column I                        Column II
(type of lever)                (example)
I. First class                   1. Joint between first vertebra and skull
II. Second class              2. Human body resting on toe
III. Third class                3. Elbow joint
Codes:
      I     II    III
A.   1     2     3
B.   2     1     3
C.   2     3     1
D.   3     2     1

In the given diagram of the lower limb bones of a human, a sesamoid bone is depicted by the letter:
   
1. A
2. B
3. C
4. D

In the molecule shown in the given diagram, ATPase activity is present in:
   
1. A
2. B
3. C
4. D

What masks the active sites for myosin head present on the actin myofilaments?
1. Light meromyosin
2. Heavy meromyosin
3. G – actin
4. Troponin

Ribs 11 and 12 are called floating ribs because they
1. do not articulate with the vertebrae
2. attach only indirectly to the sternum
3. have no connection to the sternum
4. do not articulate directly with any other bone

The depression on the coxa where the head of the femur articulates is the
1. acetabulum.
2. auricular surface.
3. iliac fossa.
4. ischial tuberosity.

The ability of a muscle fiber action potential to cause an increase in cytosolic calcium concentration is dependent upon
1. The conduction of action potentials down T-tubules which are in intimate contact with the sarcoplasmic reticulum.
2. The presence of the voltage sensitive protein called the ryanodine receptor in the T-tubule membrane
3. The calcium channel protein called the dihydropyridine receptor which is located in the sarcoplasmic reticulum membrane
4. Ca++-ATPase pumps in the sarcoplasmic reticulum

When a skeletal muscle shortens during contraction which of these statements is false?
1. The l-band shortens
2. The A-band shortens
3. The H-zone becomes narrow
4. The sarcomeres shorten

Which of the following is not a feature of red muscle fibres?
1. They have plenty of mitochondria.
2. They have a high content of Myoglobin.
3. They have a high amount of Sarcoplasmic reticulum.
4. They are called aerobic muscles.

During resting stage the binding site of actin for myosin remains masked by
1. Troponin                2. Gactin
3. Tropomyosin          4. Meromyosin