STUDY GUIDE CHAPTERS 48 and 50
THE NERVOUS SYSTEM
SENSORY AND MOTOR NEURONS
To Accompany Campbell 9th Ed
The entire chapter 48 is important, is emphasized on the AP Exam, and can be tested
in class. We will address Chapter 49 in class. We will do selections from Chapter 50.
i. How does the cone snail disable its prey?
ii. Communication by the nervous system consists of long distance __________________
and short-distance __________________
iii. Less complex than a brain, clusters of neurons are called ________________.
CONCEPT 48.1
NEURON ORGANIZATION AND STRUCTURE REFLECT FUNCTION IN INFORMATION TRANSFER.
A. Draw two neurons in a series, Fig 48.4. If there are any terms you do not know,
define them. The terms on page 1046 are basic to this chapter.
CONCEPT 48.2
ION PUMPS AND ION CHANNELS ESTABLISH THE RESTING MEMBRANE POTENTIAL.
B.? -60 to – 80mV is the _______________ potential of a typical resting neuron
*We will use -70 mV as a reference number.
C. Draw a blown-up resting neuron, showing the distribution of ions inside and
outside of the neuron. (Fig 48.7)
In a resting neuron, there is a higher percentage of sodium (inside/ outside the cell).
There is a higher percentage of potassium (inside/ outside the cell).
Note: The modeling of the resting potential and the Nernst Equation are not within the scope of this
class. In case you are wondering, however, 62 mV is a constant that comes from RT/ zF (z= valence of
the ion; F is Faraday’s constant.)
CONCEPT 48.3
ACTION POTENTIALS ARE THE SIGNALS CONDUCTED BY AXONS
D. Read this section and take notes about the new concepts and bold-faced words.
E. Figure 48.11 The role of voltage-gated ion channels in the generation of an action
potential. This picture tells everything about the action potential.
1. Draw the graph in the center.
2. Inspect the drawing that goes with each label, and write the caption for each
label. Trust me, this is important!!
CONCEPT 48.4 NEURONS COMMUNICATE WITH OTHER CELLS AT SYNAPSES
F. Figure 48.15 A Chemical Synapse. Look at the picture and write the 4 events that
occur at the chemical synapse.
G. Define EPSP and IPSP. An EPSP brings the membrane potential closer to
threshold, and the IPSP brings the membrane potential further from threshold.
Which makes an action potential more likely?
H. Neurotransmitters do not stay in the synaptic cleft for long. What can clear the
cleft of neurotransmitter?
I. What does summation of EPSP (IPSP) mean? What does temporal refer to?
ie: “temporal summation”, or (“temporal isolation” from Chapter 24).
How does temporal summation differ from spatial summation.
J. Modulated signaling at synapses. Summarize the events that occur when
norepinephrine binds to its metabotropic receptor.
K. After reading about Neurotransmitters, make a list of the functions of each:
Acetylcholine, Glutamate, GABA, Norepinephrine, Dopamine, Serotonin, Substance P,
Endorphins, Nitric Oxide (NO)
*Think about this: How might a brain researcher investigate the function of different
areas of the brain, without using electrodes or invasive surgery?
We will discuss Nervous Systems, Chapter 49, in class.
In Chapter 50, Sensory and Motor Mechanisms, it is more important to learn
about general sensory and motor mechanisms than to learn details about each sense
organ. Therefore, answer these questions, but you do not need to read the whole
chapter.
L. What is meant by sensory receptor?
M. Define mechanoreceptor and give 3 examples.
N. Define chemoreceptor and give 6 examples.
O. Define electromagnetic receptor and list 4 organisms that use this.
P. What was learned from capsaicin about “hot” tasting food. What flavor tastes
“cool’.
Q. Look at Fig 50.4. What are the two ways that the stimulus intensity can increase?
*What is the significance of the squirrel monkey shown on page 1100.
CRASH COURSE, MUSCLE FUNCTION
R. Watch the fascinating and entertaining Crash Course “Muscular System” (“Big
Guns, Muscular System”) http://www.youtube.com/watch?v=jqy0i1KXUO4
S. You should be familiar with the names of the structures: Actin and Myosin, and
the role of Calcium.
T. Can you name THREE events in muscle contraction/ relaxation that use ATP?