Arrange the following events in correct chronological order:
a: | acetylcholine hydrolyses into acetate and choline |
b: | acetylcholine diffuses across the synaptic cleft |
c: | Impulse reaches the terminal endings of the motor neuron |
d: | acetylcholine binds to its receptor on motor end plate |
e: | sarcolemma gets depolarized |
1. | b, c, d, a, e | 2. | c, b, d, e, a |
3. | c, d, b, a, e | 4. | d, e, b, a, c |
Study the events given below. Identify the set given in the choice that has the events in correct chronological order of their occurrence:
a. Ca2+ combines with tropomyosin
b. Ca2+ combines with troponin
c. tropomyosin pulls away from actin
d. troponin pulls away from actin
e. tropomyosin pulls away from myosin
f. troponin pulls away from myosin
g. myosin binds to actin
1. | a, d, g | 2. | b, e, f |
3. | a, c, g | 4. | b, c, g |
A muscle cell is called as a:
1. | sarcomere | 2. | fiber |
3. | myofibril | 4. | myofilament |
The Z line is present in:
1. | A band | 2. | H zone |
3. | I band | 4. | M line |
The joint between skull bones is classified as:
1. | cartilaginous | 2. | fibrous |
3. | epithelial | 4. | synovial |
The part of the sarcomere that is composed of only myosin myofilaments is:
1. | A band | 2. | I band |
3. | M line | 4. | H zone |
A neuromuscular disorder that causes weakness in the skeletal muscles is:
1. | poliomyelitis | 2. | myasthenia gravis |
3. | multiple sclerosis | 4. | muscular dystrophy |
What happens during the contraction of a skeletal muscle fiber?
1. | The myosin filaments stay the same size but the actin filaments shorten |
2. | The sarcomeres shorten |
3. | The actin filaments stay the same size but the myosin filaments shorten |
4. | Both actin and myosin filaments shorten |
What is number of bones in a human adult?
1. | 150 | 2. | 300 |
3. | 250 | 4. | 206 |
Cross bridge formation during muscle contraction involves:
1. | troponin and actin | 2. | tropomyosin and myosin |
3. | myosin and troponin | 4. | myosin and actin |