The H-Zone in the skeletal muscle fibre is due to
(1) the central gap between actin filaments extending through myosin filaments in the A-band
(2) extension of myosin filaments in the central portion of the A-band
(3) the absence of myofibrils in the central portion of A-band
(4) the central gap between myosin filaments in the A-band
Consider the diagram given below.
Parts labelled as A, B, C, D, E and F respectively indicate.
(1) Sacrum, ilium, pubis, femur, tibia and fibula
(2) Ilium, pubis, sacrum, femur, fibula and tibia
(3) Sacrum, pubis, ilium, femur, tibia and fibula
(4) Ilium, sacrum, pubis, femur, tibia and fibula
Pick out the correct match
(1) Sternum - 14
(2) Pelvis - 3
(3) Ribs - 20
(4) Face - 5
Match Column-I with Column-II:
Column-I | Column-II |
A. Structural and functional unit of a myofibril B. Protein of thin filament C. Protein of thick filament D. The central part of thick filament not overlapped by thin filament |
I. H-zone II. Myosin III. Sarcomere IV. Actin |
(1) A - I, B - II, C - III, D - IV
(2) A - I, B - III, C - II, D - IV
(3) A - I, B - IV, C - III, D - II
(4) A - III, B - IV, C - II, D - I
Light bands (thin filaments) contain actin and are called:
(1) A-bands or Isotropic band
(2) A-bands or Anisotropic bands
(3) I-bands or Isotropic bands
(4) I-bands or Anisotropic bands
Dark bands (thick filaments) contain myosin and are called:
(1) A-bands or Isotropic band
(2) A-bands or Anisotropic bands
(3) I-bands or Isotropic bands
(4) I-bands or Anisotropic bands
Choose the letter from the figure that most appropriately corresponds to the structure:
I.A-band II. I-band III. Sarcomere IV. H-zone
V.Myosin VI.Actin, Troponin, Tropomyosin VII. Z –line
(1) I - E, II - D, III - F, IV - G, V - B, VI- C, VII - A
(2) I - E, II - D, III - C, IV - G, V - B, VI - A, VII - F
(3) I - E, II - D, III - F, IV - G, V - C, VI - A, VII - B
(4) I - E, II - D, III - F, IV - A, V - B, VI - C, VII - G
Ca+2 bind ________ in the skeletal muscles and leads to exposure of the binding site for ________ on the filament _______:
(1) Troponin, myosin, actin
(2) Troponin, actin, relaxin
(3) Actin, myosin, troponin
(4) Tropomysin, myosin, actin
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