Sarcomere is the area between:
(1) 2 H-zones
(2) 2 Z-lines
(3) 2 M-lines
(4) 2 A-bands
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
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
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
The action potential that triggers a muscle contraction travels deep within the muscle cell by means of:
(1) Sarcoplasmic reticulum
(2) Transverse tubules
(3) Synapse
(4) Motor end plates
ATP provides energy for muscle contraction by allowing for:
1. An action potential formation in the muscle cell
2. Cross-bridge attachment of myosin to actin
3. Cross-bridge detachment of myosin from actin
4. Release of Ca+2 from sarcoplasmic reticulum