A patient scheduled for surgery confides in his nurse the night before that he is 'terribly scared.' Which of the following indicate(s) increased sympathetic activity in this patient:

Correct Answer: D

Rationale: All are sympathetic 'fight-or-flight' signs: dry mouth (reduced salivation), sweating (stress response), pale skin (vasoconstriction), dilated pupils (adrenergic).

Correct Answer: C

Rationale: Microglia act as the CNS immune cells, phagocytosing debris and pathogens, similar to white blood cells. Oligodendrocytes myelinate, astrocytes support, ependymal cells line ventricles, lymphocytes are immune system cells.

Correct Answer: A

Rationale: Dendrites receive signals and conduct them toward the neuron’s cell body. Axons carry impulses away, synapses transfer between neurons.

Correct Answer: A

Rationale: Nervous system responses are rapid, precise, and localized (e.g., reflexes), unlike the slower, diffuse, longer-lasting endocrine system (hormones).

Correct Answer: C

Rationale: Acetylcholine and norepinephrine are well-known neurotransmitters. Options A and B are DNA/RNA bases, not transmitters.