The majority of the muscle fibers in the skeletal muscles of the leg of a long distance runner is expected to have:
1. adaptation for sudden outburst of activity
2. primarily anaerobic source of energy
3. numerous mitochondria
4. large deposits of glycogen
During relaxation in smooth muscle:
1. calcium is removed from troponin.
2. bind to calmodulin.
3. myosin phosphatase removes phosphate from myosin.
4. Calcium is released from the sarcoplasmic reticulum.
Cylindrical, branched muscle cells that are arranged into functional syncytium are:
1. cardiac muscles.
2. skeletal muscles.
3. single unit smooth muscles.
4. multi unit smooth muscles.
A muscle cell is called as a:
1. | sarcomere | 2. | fiber |
3. | myofibril | 4. | myofilament |
All the following are parts of the actin myofilament in a sarcomere except:
1. actin
2. cisternae
3. tropomyosin
4. troponin
An ATPase activity is associated with:
1. G actin molecule
2. head of myosin molecule
3. troponin molecule
4. F actin
Overlap between actin and myosin myofilaments in a sarcomere is seen in:?
1. A band
2. H zone
3. I band
4. M line
The Z line is present in:
1. | A band | 2. | H zone |
3. | I band | 4. | M line |
The drug curare causes:
1. flaccid paralysis.
2. spastic paralysis.
3. smooth muscle degeneration.
4. cardiac failure.
A motor unit is
1. | all the muscle fibers innervated by all the motor neurons in a muscle. |
2. | all the fibers in one fasciculus. |
3. | all the muscle fibers innervated by a single motor neuron in a muscle. |
4. | all the motor neurons that innervate one muscle fiber in a muscle. |