Sarcomere

Q. Define sliding filament theory of muscle contraction.

Q. The thick filament consists of ---------

1. G Actin
2. myosin
3. troponin
4. tropomyosin

Q. Which of the following pairs of chemical substances, is correct categorization

1. Calcitonin and thymosin - thyroid hormones
2. Pepsin and prolactin - two digestive enzymes secreted in stomach
3. Troponin and myosin - complex proteins in striated muscles
4. Secretin and rhodopsin - Polypeptide hormones

Q.

The functional unit of contractive system in striated muscle is______.

1. Cross bridges

2. Myofibril

3. Sarcomere

4. Z-band

Q.

Thick and thin filaments form the (i)__________. The thick and thin filaments overlap and form a definite pattern that form repeating units called (ii)______.

1. (i) myofibrils (ii) sarcomere

2. (i) sarcomere (ii) myofibrils

3. (i) fascia (ii) fascicle

4. (i) fascicle (ii) fascia

Q. When muscles are at rest, thin filaments overlap with thick filaments

1. inside I-band
2. inside M-line
3. outside H-zone
4. inside Z-line

Q. Sliding filament theory can be best explained as:

1. Actin and myosin filaments do not shorten but rather slide each other
2. When myofilaments slide each other, myosin filaments shorten while actin filaments do not shorten
3. When myofilaments slide each other actin filaments shorten while myosin filament do not shorten
4. Actin and myosin filaments shorten and slide each other

Q.

The region made of thin filaments is _______ .

1. A band

2. I band

3. Z line

4. H band

5. M Line

Q. The H-Zone in the skeletal muscle fiber is due to

1. The central gap between the 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 the myosin filaments in the A-band

Q. State whether the given statement is true or false.

Q.

Myosin myofilaments are

1. Attached to the Z–disk

2. Absent from the H–zone

3. Found primarily in the I–band

4. None of the above

Q.

Choose the correct option to label the following parts

1. 1.Thin filament 2.Thick filament 3.Sarcomere

2. 1.Thick filament 2.Thin filament 3.Sarcomere

3. 1.Sarcomere 2.Thick filament 3.Thin filament

4. 1.Sarcomere 2.Thin filament 3.Thick filament

Q.

Draw the diagram of a sarcomere of skeletal muscle showing different regions.

Q.

Match Column I with Column II :

	Column I		Column II
(a)	Smooth muscle	(i)	Myoglobin
(b)	Tropomyosin	(ii)	Thin filament
(c)	Red muscle	(iii)	Sutures
(d)	Skull	(iv)	Involuntary