NEET 2021
- Exam
- NEET
- Year
- 2021
- Subject
- Zoology
- Chapter
- Locomotion and Movement
NEET 2021 · Zoology · Locomotion and Movement
During muscular contraction which of the following events occur?...
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.
(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.
Options
- A(a), (c), (d), (e) only
- B(a), (b), (c), (d) only
- C(b), (c), (d), (e) only
- D(b), (d), (e), (a) only
Correct answer
A. (a), (c), (d), (e) only
Step-by-step solution
The following events take place during muscular contraction.
(1) Myosin hydrolysis ATP into ADP and Pi. The energy released is used to make a cross-bridge with actin filaments. This pulls the actin filaments towards A-band.
(2) 'Z' line attached to these actins are also pulled inwards thereby causing the shortening of the I-band and thus the sarcomere.
(3) The size of the A-band remains constant.
(4) The movement of actins towards the A-band, causes H-zone to disappear.