Class 2: Introduction to Neurophysiology

Question 1

Describe the main components of the central and peripheral nervous system, and their general functions.

Answer 1

CNS: brain and spinal cord
Function: the body’s major integration center

PNS: nerves that branch out from the CNS
Function: sends information to the CNS and relays information from the CNS to effectors

Question 2

Describe the divisions of the peripheral nervous system.

Answer 2

1. Somatic
2. Autonomic (sympathetic, parasympathetic, enteric)

Question 3

Differentiate between the afferent and efferent divisions of the peripheral nervous system. Describe the general function and direction of information flow for each.

Answer 3

Afferent: sensory information flows from the PNS to the CNS
1. Somatic (touch, pain, temperature)
2. Special (vision, hearing, equilibrium, smell, taste)
3. Visceral (blood pressure, pH, osmolarity)

Efferent: motor information flows from the CNS to effectors via peripheral nerves
1. Visceral (to involuntary muscle and glands)
2. Somatic (to skeletal/voluntary muscle)

Question 4

Describe the structure and function of the different components of a neuron (i.e. dendrites, soma, axon).

Answer 4

Dendrites - branched processes that extend from the soma, receive input signals from other neurons or stimuli in the environment

Soma - contains the organelles, control center of the neuron (CNS = nucleus, PNS = ganglia)

Axon - thin process extending from the soma, output portion, generates action potentials

Axon Hillock - trigger zone, where action potentials start

Axon Terminal - responsible for synaptic transmission, neurotransmitters are sent to vesicles

Question 5

Compare and contrast the morphology of sensory neurons (unipolar) with that of motor neurons and interneurons (multipolar). Describe the direction of signal transmission in these different cell types.

Question 6

Describe the organization of the spinal cord with respect to the function of the dorsal and ventral roots and their relationship to the efferent and afferent divisions of the peripheral nervous system.

Question 7

Explain how the size and proportion of the grey and white matter differ at different levels of the spinal cord (sacral, lumbar, thoracic, cervical)

Question 8

Summarize the main functions of the brainstem (pons, medulla oblongata, midbrain).

Question 9

Summarize the main functions of the diencephalon (thalamus, hypothalamus, pineal gland, pituitary gland).

Question 10

Summarize the main functions of the cerebellum.

Question 11

Summarize the main functions of the cerebrum (cortex and basal nuclei).