Question

what receives stimuli from receptor sites in the sensory organs and transmits them to the brain and spinal cord?
○ efferent neuron
○ associative neuron
○ afferent neuron
○ glial cell
question 2 (2 points)
what is a mixed nerve?
○ a nerve containing both sensory and motor fibers.
○ a nerve that originates in the brain and brain stem.
○ a network of spinal nerves and veins.
○ a nerve that originates from the spinal cord.

Explanation:

Question 1

• Efferent neuron: Transmits signals from brain/spinal cord to effectors (not sensory to CNS).
• Associative neuron: Connects neurons within CNS (not sensory input).
• Afferent neuron (sensory neuron): Receives stimuli from sensory organs and sends to CNS (brain/spinal cord).
• Glial cell: Supports neurons, not involved in signal transmission for sensory input.

• Option 1: Mixed nerves have both sensory (afferent) and motor (efferent) fibers (matches definition).
• Option 2: Cranial nerves originate in brain/brainstem, but this doesn’t define mixed nerve.
• Option 3: Nerves and veins are different; mixed nerve isn’t a network of them.
• Option 4: Spinal nerves originate from spinal cord, but this doesn’t define mixed nerve.

Answer:

C. Afferent neuron

Question 2