Problem:

Animal physiology! Please help!

Question 1: Each retina contains a finite (and large) population of ganglion cells. For the sake of simplicity, assume the majority of these enable vision whereas a minority enable reflex turning of the head as well as the pupillary light reflex. Therefore, in the case of the majority, where does neurosecretion occur?

(a) midbrain nuclei,

(b) thalamic nuclei, or

(c) sensory cortex.

Question 2: Identify the muscle that enables the motor component of the pupillary light reflex.

(a) extrinsic eye muscles,

(b) intrinsic eye muscles, or

(c) sphincter muscle of the iris.

Question 3: Consider reflex turning of the head and the pupillary light reflex. Does the central integration that enables these reflexes occur within the same region of the CNS?

(a) yes, the midbrain, or

(b) no.

Question 4: Which fiber tract enables reflex turning of the head?

(a) medial longitudinal fasciculus,

(b) tectospinal, or

(c) corticospinal.

Question 5: The tectospinal tracts are:

(a) limited to the cervical cord, or

(b) found throughout the length of the cord.

Question 6: How would you characterize the pupillary light reflex?

(a) parasympathetic,

(b) autonomic,

(c) cranial, or

(d) all of the above.

Question 7: How would you characterize reflex turning of the head?

(a) parasympathetic,

(b) autonomic,

(c) cervical, or

(d) all of the above.

Question 8: How would you characterize reflex-based allocation of arterial blood?

(a) autonomic,

(b) parasympathetic autonomic, or

(c) sympathetic autonomic.

Question 9: Autonomic reflexes are categorized by the level from which motor output leaves the CNS. Parasympathetic motor output leaves the CNS only from the:

(a) brainstem and pelvic cord,

(b) thoracolumbar spinal cord, or

(c) cervical spinal cord.

Question 10: Sympathetic motor output leaves the CNS from the:

(a) brainstem and pelvic cord,

(b) thoracolumbar spinal cord, or

(c) cervical spinal cord.

Give reasoning with your answer.