Sarcomere is described as the part of myofibril between two

(1) M-lines

(2) Z-lines

(3) A-bands

(4) I-bands

Unit of contraction in a muscle fiber is:
1.  Sarcomere
2.  Muscle fiber
3.  Actin
4.  None

Match Column-I with Column-II:

(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

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

During muscular contraction, which of the following events occur?

(i)   H-zone disappears

(ii)  A band widens

(iii)  I band shortens

(iv)  Width of A band is unaffected

(v)  M line and Z line come closer

(1)  (i),(iii),(iv) and (v)

(2)  (i),(ii) and (v)

(3)  (ii),(iv) and (v)

(4)  (i),(ii) and (iii).

Read the following A to D statements and select the option that contains both correct statements:
A. Z-line is present in the centre of the light band.
B. Thin filaments are firmly attached to the M-line
C. The central part of thick filaments, not overlapped by thin filaments is called Z-band
D. Light band contains only thin filaments
(1) A and D           

(2) B and C             

(3) A and C                       

(4) B and D

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

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

Which of the following is correct about the given figure?

(1) The length of the thick and thin myofilaments has changed.

(2) Length of both anisotropic and isotropic band has changed.

(3) The myosin cross-bridges move on the surface of actin and the thin and thick myofilaments slide past each other.

(4) Length of the sacromere remains same.

Which of the following is not true regarding M line?