The globular head of the myosin filament has active site/s for binding to:
I. ATP
II. Active site on actin filament
III. Calcium
1. | Only I | 2. | Only I and II |
3. | Only II and III | 4. | I, II and III |
Skeletal muscles appear striated due to 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 colour?
Protein | Colour | Property | |
1. | Myosin | Light | Anisotropic |
2. | Actin | Dark | Anisotropic |
3. | Myosin | Dark | Isotropic |
4. | Actin | Light | Isotropic |
During muscular contraction, which of the following events occur?
(a) 'H' zone disappears
(b) 'A' band widens
(c) 'I' band reduces in width
(d) Myosin hydrolyzes ATP, releasing the ADP and Pi
(e) Z-lines attached to actins are pulled inwards
Choose the correct answer from the options given below.
1. (b), (c), (d), (e) only
2. (b), (d), (e), (a) only
3. (a), (c), (d), (e) only
4. (a), (b), (c), (d) only