BIO 181 ASU EXAM 3 Short Answers
Briefly explain why the action potential flows only from the axon hillock to the terminal
web. - CORRECT 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.
List the 4 types of glial cells and list a phrase to describe their function. - CORRECT
ANSWER-- Microglia: cleans up cellular debris
- Astrocytes: support and repair neurons
- Schwann Cells: myelinates axons of the neurons in the PNS
- Satellite: form the brain-blood barrier within the CNS
How do the glial cells (i.e., myelin sheath) speed up the firing of neurons? - CORRECT
ANSWER-The cell wraps extensions of a fatty insulating substance (myelin) around the
axons of neurons.
What could the stress of taking an exam do to your glucose levels in various parts of the
body? - CORRECT ANSWER-It can raise the glucose levels in your blood
When epinephrine is released it triggers activation of which part of the Autonomic
Nervous System? - CORRECT ANSWER-The adrenal medulla, which then triggers the
hypothalamus
Where do fats in the body play a role in balance between glucose and glycogen -
CORRECT ANSWER-When blood glucose levels fall, the pancreas stops releasing
insulin, and cells switch to using glycogen and fat for energy
Explain how insulin and glucagon regulate the balance (i.e, homeostasis) between
glycogen and glucose when epinephrine (i.e., adrenalin) is not involved. - CORRECT
ANSWER-Insulin and glucagon work in what's called a negative feedback loop. During
this process, one event triggers another, which triggers another, and so on, to keep your
blood sugar levels balanced.
During digestion, foods that contain carbohydrates are converted into glucose. Most of
this glucose is sent into your bloodstream, causing a rise in blood glucose levels. This
increase in blood glucose signals your pancreas to produce insulin.
The insulin tells cells throughout your body to take in glucose from your bloodstream. As
the glucose moves into your cells, your blood glucose levels go down. Some cells use
Briefly explain why the action potential flows only from the axon hillock to the terminal
web. - CORRECT 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.
List the 4 types of glial cells and list a phrase to describe their function. - CORRECT
ANSWER-- Microglia: cleans up cellular debris
- Astrocytes: support and repair neurons
- Schwann Cells: myelinates axons of the neurons in the PNS
- Satellite: form the brain-blood barrier within the CNS
How do the glial cells (i.e., myelin sheath) speed up the firing of neurons? - CORRECT
ANSWER-The cell wraps extensions of a fatty insulating substance (myelin) around the
axons of neurons.
What could the stress of taking an exam do to your glucose levels in various parts of the
body? - CORRECT ANSWER-It can raise the glucose levels in your blood
When epinephrine is released it triggers activation of which part of the Autonomic
Nervous System? - CORRECT ANSWER-The adrenal medulla, which then triggers the
hypothalamus
Where do fats in the body play a role in balance between glucose and glycogen -
CORRECT ANSWER-When blood glucose levels fall, the pancreas stops releasing
insulin, and cells switch to using glycogen and fat for energy
Explain how insulin and glucagon regulate the balance (i.e, homeostasis) between
glycogen and glucose when epinephrine (i.e., adrenalin) is not involved. - CORRECT
ANSWER-Insulin and glucagon work in what's called a negative feedback loop. During
this process, one event triggers another, which triggers another, and so on, to keep your
blood sugar levels balanced.
During digestion, foods that contain carbohydrates are converted into glucose. Most of
this glucose is sent into your bloodstream, causing a rise in blood glucose levels. This
increase in blood glucose signals your pancreas to produce insulin.
The insulin tells cells throughout your body to take in glucose from your bloodstream. As
the glucose moves into your cells, your blood glucose levels go down. Some cells use
