Aside from the nervous system, which other organ system develops out of the ectoderm?

Correct Answer: C

Rationale: The ectoderm gives rise to the nervous system and the integumentary system (skin, hair, nails) (C). The digestive (A) and respiratory (B) systems primarily develop from the endoderm, while the urinary (D) system arises from the mesoderm and endoderm. C is correct.

Correct Answer: C

Rationale: Autonomic ganglia (C) contain neurons regulating homeostasis (e.g., heart rate, digestion) via the autonomic nervous system. Sensory (A) and dorsal root ganglia (B) handle sensation, and cranial nerve ganglia (D) vary. C is correct.

Correct Answer: D

Rationale: In the peripheral nervous system (PNS), a bundle of axons is called a nerve. A nucleus refers to a cluster of cell bodies in the CNS, a ganglion is a cluster of cell bodies in the PNS, and a tract is a bundle of axons in the CNS.

Correct Answer: C

Rationale: Chemoreceptors detect chemical stimuli, such as molecules (e.g., odors or tastes), in the environment or body. Thermoreceptors detect temperature, not light, sound, or vibration.

Correct Answer: A

Rationale: Mechanically gated channels open in response to physical stimuli, such as pressure or stretch (e.g., in touch receptors). Chemical stimuli affect ligand-gated channels.