Which of the following has ATPase activity?
1. Actin 2. Tropomyosin
3. Head of myosin 4. Troponin
The globular head of the myosin filament has active site/s for binding to:
I. ATP
II. the binding site for actin filament
III. Calcium
1. Only I
2. Only I and II
3. Only II and III
4. I, II, and III
The contractile protein of skeletal muscle involving ATPase activity is :
1. tropomyosin
2. myosin
3. -actinin
4. troponin
Skeletal muscles appear striated due to the presence of two characteristic proteins in alternating dark and light bands. Which of the following is a correct match of the protein with its light refractive property and color?
Protein Colour Property
(1) Myosin Light Anisotropic
(2) Actin Dark Anisotropic
(3) Myosin Dark Isotropic
(4) Actin Light Isotropic
The functions of tropomyosin in skeletal muscle include:
(1) Sliding on actin to produce shortening
(2) Release Ca+2 after initiation of contraction
(3) Acting as "relaxing protein" at rest by covering up the sites where myosin binds to actin
(4) Generates ATP
Following is the figure of actin (thin) filaments. Identify A, B and C:
1. A - Tropomyosin, B - Troponin, C - F-actin
2. A - Troponin, B - Myosin, C - Tropomyosin
3. A - Troponin, B - Tropomyosin, C - Myosin
4. A - Troponin, B - Tropomyosin, C - F-actin
The above figure is related with myosin monomer (meromyosin). Identify A to C:
(1) A - head, B - cross arm, C - GTP binding sites
(2) A - head, B - cross arm, C - Ca+2 binding sites
(3) A - head, B - cross arm, C - ATP binding sites
(4) A - cross arm, B - head, C - ATP binding sites
ATPase of the muscle is located in:
(1) Actinin
(2) Troponin
(3) Myosin
(4) Actin
Which of the following is not correct?
(1) Cilia and flagella are the outgrowths of the cell membrane
(2) Flagellar movements help in the swimming of spermatozoa, maintenance of water current in the canal system of sponges
(3) Locomotion of Protozoan like Euglena is also carried by cillia
(4) 40-50 percentage of body weight of a human adult is contributed by muscles
Sarcoplasmic reticulum, sarcolemma, sarcoplasm are the features of
(1) Muscle fibre
(2) Myofibrils
(3) Myofilaments
(4) Muscle