Name: _____________________________ Date: __________ Period:
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Chapter 45: Hormones and the Endocrine System
Chapter 48-49: The Nervous System
1. What is a hormone?
2. Why does a hormone elicit a response only with specific target cells?
3. Several types of secreted signaling molecules are discussed in this chapter. State the action of each of the
following, and give an example of each
a. hormones
b. local regulators
c. neurotransmitters
d. pheromones
4. What endocrine gland secretes epinephrine? What
response(s) result from epinephrine?
5. Use the figure to the right to explain the signal
transduction pathway for epinephrine. (You may need
to review signal transduction in Chapter 11).
6. One hormone can have several different effects. For
example, epinephrine can cause the release of glucose
from liver cells, dilate blood vessels to skeletal muscles,
and constrict intestinal blood vessels. All these effects
prepare the body for “fight or flight.” Explain how these
multiple effects are possible.
7. What occurs in a negative feedback loop?
8. Complete the following chart for this pair of antagonistic hormones. Specifically note where alpha and beta
cells are involved.
Hormone Secreted By
Insulin
Glucagon
Action
9. On the AP Biology exam, you will be expected to explain a
feedback loop. Use the figure to the right to explain the control of
blood glucose by insulin and glucagon. Insulin and Glucagon are
antagonistic, this means they have opposing/opposite effects.
This is a commonly used example, and one you should know.
10. What occurs in diabetes mellitus?
11. Distinguish between type 1 diabetes and type 2 diabetes.
12. Which type of diabetes is correlated with obesity?
13. Define/describe positive feedback.
14. Explain how contractions/labor are an example of positive
feedback. Be sure to state the hormone involved and describe its
function (Ch 46).
15. What is the function of Thyroid hormone?
16. From what gland is Thyroid hormone secreted?
17. What is the cause of Graves’ Disease?
18. What are the symptoms of Graves’ Disease?
19. What is the function of Melatonin?
20. What is Circadian Rhythm?
21. What is Jet Lag. How does it affect people?
22. Provide one example of circadian rhythm in
plants (Chapter 39).
23. What is a neuron?
24. The sketch to the right shows two neurons.
Label the following elements of this figure:
cell body, dendrites, axon, synapse,
presynaptic cell, postsynaptic cell, synaptic
vesicles,
synaptic
terminal,
and
neurotransmitter.
25. What is shown in the box above? What do the red spheres represent?
26. What is indicated by the red arrows in the main figure?
27. What are glial cells?
28. All cells have a membrane potential across their
plasma membrane. What is the typical resting
potential of a neuron?
29. On the sketch to the right, label the following:
outside cell, inside cell. Show where the
concentrations of Na+ and K+ are highest.
30. How are the concentration gradients of Na+ and K+
maintained?
31. As you see in the figure above, in a resting neuron, the outside of the membrane is positively charged
relative to the inside of the membrane. If positively charged ions flow out, the difference in charge between
the two sides of the membrane becomes greater. What is the increase in the magnitude of the membrane
potential called?
32. When a stimulus is applied, ion channels will open. If positively charged ions flow in, the membrane is said
to depolarize. If depolarization causes the membrane potential to drop to a critical value, a wave of
depolarization will follow. What is this critical value called?
33. What is the wave of depolarization called?
34. Just like toppling dominoes in a row, either the threshold of depolarization will be reached and an action
potential will be generated, or the threshold will not be reached and no wave will occur. What is this
response to stimulus called?
35. Figure 48.10 contains almost all you need to know about nerve impulse transmission, so it is worth some
careful study time. Let’s approach it in steps.
a. Label Na+, K+, and their respective ion channels.
b. Label the Resting state figure. Are the Na+ and K+ channels open, or closed?
c. Label Depolarization. What triggers depolarization? What channels open? What occurs if the
depolarization threshold is reached?
d. Label Stage 4 in the figure Repolarization. How is the charge on the membrane reestablished?
e. Label these regions of the graph: x- and y-axes, threshold, resting potential, depolarization, action
potential, and repolarization.
f. Let’s see if you really understand this concept. Draw in another line on the graph to show what the
change in membrane potential would look like if a stimulus were applied that did not reach the
depolarization threshold.
36. Here is a closer look at what is happening along the membrane as a wave
of depolarization (an action potential) travels along the length of the axon.
Label the key elements of the figure; and to the right, explain how the
action potential is conducted.
37. What are the two types of glial cells that produce myelin sheaths?
38. How does a myelin sheath speed impulse transmission? Include a
discussion of saltatory conduction and nodes of Ranvier in your response.
39. In the disease multiple sclerosis, the myelin sheaths harden and
deteriorate. How would this affect nervous system function?
40. When the wave of depolarization arrives at the synaptic terminal, calcium
ion channels open. What occurs to the synaptic vesicles as the Ca2+ level
increases?
41. What is contained within the synaptic vesicles?
42. Explain how an action potential is transmitted from one cell to another across a synapse by summarizing
what is shown above in six steps.
43. Explain the difference between a stimulatory response that creates an Excitatory Postsynaptic potential
(EPSP) and an inhibitory response that creates an Inhibitory Postsynaptic Potential (IPSP).
44. Select one neurotransmitter from the following list; describe the following: structure, functional class,
secretion site, function/response produced.
 acetylcholine
 norepinephrine
 serotonin
 epinephrine
 dopamine
 GABA
45. Identify the portion of the brain that controls one of the following. How is the brain involved in controlling
this function?
 muscle movement
 hearing
 vision
 abstract thought and emotions
46. For either a or b, describe each of the brain parts listed. Compare and contrast their functions.
a. forebrain (cerebrum), midbrain (brainstem), hindbrain (cerebellum)
b. Right and left cerebral hemispheres in humans.