Part A: Multiple Choice
1. What type of nerve cell returns the body to normal resting levels after adjustments to stress?
2. Immunity is:
a) guard against a wide variety of pathogens (disease causing agents)
b) the ability to resist a disease after being exposed to it in the past
c) having no allergies
d) the ability to recognize and engulf antigens (invading organisms)
3. What is the membrane of an axon called when it is charged by unequal distribution of positively charged ions inside and outside the nerve cell?
4. A person suffers a stroke that results in a loss of speech, difficulty in using the right arm, and an inability to solve mathematical equations. Which area of the brain was damaged?
a) left cerebellum
b) left cerebral hemisphere
c) medulla oblongata
d) right cerebral hemisphere
e) right cerebellum
5. What is the primary function of the myelin sheath?
a) to conduct active transport of potassium ions;
b) to carry wastes from the axon;
c) to regulate the diffusion of sodium ions across the synapse;
d) to increase the speed at which nerve impulses travel;
e) to supply nutrients to the axon.
Part B: Matching
Match the following words with the correct definition or function:
1. myelin sheath
2. Schwann cell
3. nodes of Ranvier
6. reflex arc
a) an insulated covering over a nerve cell
b) gaps between section of myelin sheath along the axon
c) conducts nerve impulses towards the cell body
d) type of glial cell that produces the myelin sheath
1. sensory neuron
2. action potential
5. refractory period
6. autonomic nerves
a) part of the neuron; an extension of cytoplasm that carries nerve impulses away from dendrites
b) nerve impulses caused by the reversal of charge across a nerve membrane
c) motor nerves, not under conscious control, designed to maintain homeostasis
d) a neurotransmitter that permits the transmission of an action potential across a synapse
e) carries information about the environment to the brain
f) a reflex that makes adjustments for near and distant objects
g) the time required before another action potential can be produced