BIO 181 (CAPCO ASU) EXAM 3
Q&As with Complete Solutions
Briefly explain why the action potential flows only from the axon hillock to the terminal
web. - ANSWER The action potential originates from the axon hillock which initiates the
flow of the action potential because of the presence of higher density voltage-gated ion
channels.
T/F Acetylcholine exocytosed from the presynaptic cell travels to the postsynaptic cell to
start the action potential in the postsynaptic cell. - ANSWER True
How do the glial cells (i.e., myelin sheath) speed up the firing of neurons? -
ANSWER The cell wraps extensions of a fatty insulating substance (myelin) around
the axons of neurons which increase the speed because the action potential jumps
from each node of ranvier rather than going down the entire length and firing each
Na+K+ pump.
The terminal web: - ANSWER Is a site of exocytosis
,T/F Potassium ions are at high concentrations inside of cells including in neurons.
- ANSWER True
T/F Excitatory synapses make the post-synaptic cell less likely to fire. - ANSWER False
T/F Vitamin D is synthesized from cholesterol - ANSWER True
When epinephrine is released it triggers activation of which part of the Autonomic Nervous
System? - ANSWER Sympathetic Nervous System.
T/F Insulin is produced by alpha cells. - ANSWER False
, T/F When the Sympathetic nervous system is triggered glycogen is broken down to glucose
to provide more energy. - ANSWER True
T/F The medulla of the adrenal gland produces epinephrine (i.e., adrenaline). -
ANSWER True
Your mom came back from her medical appointment and said that the M.D. told her
she had low bone density. What medical problem could this cause and what
hormones/endocrine glands in the body are involved? - ANSWER This could cause
Osteoporosis and the parathyroid is involved in this.
T/F Vitamin D causes the parathyroid to inhibit new PTH synthesis. - ANSWER True
T/F Insulin is a ligand. - ANSWER True
What could the stress of taking an exam do to your glucose levels in various parts of the
body? - ANSWER Stress can cause your sympathetic nervous system to turn on "the fight
or flight response" activating stored glycogen in your cells, thusly raising your blood
sugar levels.
Q&As with Complete Solutions
Briefly explain why the action potential flows only from the axon hillock to the terminal
web. - ANSWER The action potential originates from the axon hillock which initiates the
flow of the action potential because of the presence of higher density voltage-gated ion
channels.
T/F Acetylcholine exocytosed from the presynaptic cell travels to the postsynaptic cell to
start the action potential in the postsynaptic cell. - ANSWER True
How do the glial cells (i.e., myelin sheath) speed up the firing of neurons? -
ANSWER The cell wraps extensions of a fatty insulating substance (myelin) around
the axons of neurons which increase the speed because the action potential jumps
from each node of ranvier rather than going down the entire length and firing each
Na+K+ pump.
The terminal web: - ANSWER Is a site of exocytosis
,T/F Potassium ions are at high concentrations inside of cells including in neurons.
- ANSWER True
T/F Excitatory synapses make the post-synaptic cell less likely to fire. - ANSWER False
T/F Vitamin D is synthesized from cholesterol - ANSWER True
When epinephrine is released it triggers activation of which part of the Autonomic Nervous
System? - ANSWER Sympathetic Nervous System.
T/F Insulin is produced by alpha cells. - ANSWER False
, T/F When the Sympathetic nervous system is triggered glycogen is broken down to glucose
to provide more energy. - ANSWER True
T/F The medulla of the adrenal gland produces epinephrine (i.e., adrenaline). -
ANSWER True
Your mom came back from her medical appointment and said that the M.D. told her
she had low bone density. What medical problem could this cause and what
hormones/endocrine glands in the body are involved? - ANSWER This could cause
Osteoporosis and the parathyroid is involved in this.
T/F Vitamin D causes the parathyroid to inhibit new PTH synthesis. - ANSWER True
T/F Insulin is a ligand. - ANSWER True
What could the stress of taking an exam do to your glucose levels in various parts of the
body? - ANSWER Stress can cause your sympathetic nervous system to turn on "the fight
or flight response" activating stored glycogen in your cells, thusly raising your blood
sugar levels.
