Author Question: Stepping out of a mall and into the sunshine has caused a man's pupils to constrict. Place the ... (Read 66 times)

kshipps · **on:** Jun 25, 2018

Stepping out of a mall and into the sunshine has caused a man's pupils to constrict. Place the following anatomical components of the man's pupillary reflex in the ascending chronological order that they responded to the light. Use all the options.

A) Oculomotor nuclei
B) Retinal ganglionic cells
C) Preganglionic neurons
D) Pretectal nuclei

Question 2

Which of the following statements about over-the-counter (OTC) melatonin is accurate?

A)
It has received the FDA approval for effectiveness as a sleep aid.
B)
Long-term studies of melatonin conclude that it is nonaddicting.
C)
It produces phase-shifting changes in the circadian rhythm.
D)
Under strict clinical testing, potency and purity of melatonin have been shown to be consistent.

courtney_bruh · **Reply #1 on:** Jun 25, 2018

Answer to Question 1

Ans:
B, D, C, A

Feedback:

Pretectal areas on each side of the brain are connected, explaining the binocular aspect of the light reflex. The afferent stimuli for pupillary constriction arise in the ganglionic cells of the retina and are transmitted to the pretectal nuclei at the junction of the thalamus and the midbrain and from there to preganglionic neurons in the oculomotor (CN III) nuclei via the pretectooculomotor tract.

Answer to Question 2

Ans:
C

Feedback:

Administration of melatonin produces phase-shifting changes in the circadian rhythm similar to those caused by light. Synthetic forms of melatonin are available without prescription in health food stores and pharmacies. However, synthetic forms of melatonin are not regulated by the FDA; therefore, their potency, purity, safety, and effectiveness cannot be ensured. There is a lack of clinical trial evidence about dosage, adverse effects, and drug interactions with over-the-counter forms of melatonin.