Question

QUESTION 73
What carries motor commands from the brain along the spinal cord?
       a. Spinal nerves
       b. Descending tracts
       c. Ascending tracts
       d. Both ascending and descending tracts
       e. None of the these.

QUESTION 74
Which of the following statements is FALSE?
       a. Taste signals travel from the tongue through the facial and hypoglossal nerves.
       b. The middle ear consists of an air-filled chamber.
       c. Rods secrete glutamate from the base of the cell when NOT exposed to light.
       d. Peptide hormones are synthesized by the rough endoplasmic reticulum.
       e. None of the these.

QUESTION 75
Neurosomas of the ventral root are located in the __, whereas neurosomas of the dorsal root are located in the ___ .
       a. posterior root ganglion; gray matter
       b. posterior root ganglion; white matter
       c. gray matter; posterior root ganglion
       d. posterior horn; anterior horn
       e. white matter; posterior root ganglion
       f. None of the these.

QUESTION 76
In what region do the ventral rami of the spinal nerves NOT form nerve plexuses?
       a. the cervical region.
       b. the sacral region.
       c. the thoracic region.
       d. the lumbar region.
       e. the brachial region.
       f. None of the these.

QUESTION 77
A neuron whose axon synapses in the adrenal medulla is a __ neuron, and releases the neurotransmitter ___ .
       a. somatic; norepinephrine (NE)
       b. preganglionic; acetylcholine (ACh)
       c. postganglionic; norepinephrine (NE)
       d. postganglionic; acetylcholine (ACh)
       e. preganglionic; norepinephrine (NE)
       f. None of the these.

QUESTION 78
A major difference between smooth muscle fibers and skeletal muscle fibers in terms of calcium influx is that ____.
       a. calcium ions are stored in the sarcoplasm of skeletal muscle
       b. calcium ion influx occurs mostly from the extra cellular fluid in smooth muscle
       c. smooth muscle contraction does not involve calcium
       d. Both (i) calcium ions are stored in the sarcoplasm of skeletal muscle and (ii) calcium ion influx occurs mostly from the extra cellular fluid in smooth muscle.
       e. None of the these.

Answer 1

Ans 1-descending tracts

The descending tracts are the pathways by which motor signals are sent from the brain to lower motor neurones.

Ans2- Rods secrete glutamate from the base of the cell when NOT exposed to light

Ans 3-  posterior root ganglion; gray matter

Ans 4- the thoracic region.

, the anterior rami of most of the thoracic spinal nerves do not form a plexus, instead they are called the intercostal nerves and they run along the intercostal spaces.

Ans 5- postganglionic; acetylcholine (ACh)

Ans 6- calcium ion influx occurs mostly from the extra cellular fluid in smooth muscle