13. The Peripheral Nervous System

Owen is a grad student who does research on sensory receptors. When classifying receptors, he organizes them based on if respond to external or internal stimuli. Owen is classifying receptors by:

Which parts of the body have the greatest amount of space dedicated to them in the primary somatosensory cortex? Why?

The cell bodies of upper motor neurons reside in the ________ and function to ________, whereas the cell bodies of lower motor neurons reside in the ________ and function to ________.

A receptor potential:

a. Always leads to an action potential

b. Never leads to an action potential

c. Causes hyperpolarization of the neuron

d. Leads to an action potential if the stimulus is strong enough

Merkel cell fibers, tactile corpuscles, Ruffini endings, and lamellated corpuscles are all types of:

a. Nociceptors

b. Mechanoreceptors

c. Photoreceptors

d. Chemoreceptors

Predict what might happen if nociceptors were rapidly adapting instead of slowly adapting receptors. Would this change be beneficial or potentially harmful?

Mark the following statements as true or false. If a statement is false, correct it to make a true statement.

b. Thermoreceptors send temperature information to centers in the hypothalamus.

Ascending tracts

(a) Carry sensory information to the brain,

(b) Carry motor information to the brain

(c) Carry sensory information from the brain

(d) Carry motor information from the brain

(e) Connect perceptive areas with the brain

Tactile nerve endings, tactile corpuscles, bulbous corpuscles, and lamellated corpuscles are all types of:

a. Nociceptors

b. Mechanoreceptors

c. Photoreceptors

d. Chemoreceptors

Which of the following is true of the autonomic, but not the somatic, nervous system?

a. Neurotransmitter is acetylcholine

b. Axons are myelinated

c. Effectors are muscle cells

d. It has motor neurons located in ganglia