Test 1 Analysis

1
Test 1 Analysis
Endo Glucose Thermo Neuro ShortAnswer Hiking Overall
Avg 77 85 83 76 84 85 80
Stdev 10 13 14 13 11 9 8
Median 77 89 85 76 88 87 81
Max 92 100 100 100 100 100 95
2
This Week in Physiology

• Class

• Lab

• Finish Chapter 6 DNervous System
• Do Chapter 7 Sensory Physiology

• Visual System Part 1
• PPT is posted to password protected website
• Text p. 202-212
• Sensory Physiology
• Cutaneous sites sensitive to four modalities

3
Anatomy of an Electrical Synapse (aka Gap
Junction)
S 1
S 8

• Comparison to Chemical Synapses
• Directionality
• Response time
• Sign inversion?

Uncommon in human CNS.Common in cardiac
muscleand some smooth muscle.
4
Figure 6.28
S 2
Some ion Channels that allow flux of Na and K
simultaneously e.g. nicotinic Acetylcholine
Receptor (nAChR)
EPSPs which ion moving in which
direction? Duration of PSP vs AP Synaptic delay
Exercise, Hypokalemia, andSports Drinks
5
Figure 6.29
S 3
IPSPs which ion moving in which direction?
Some IPSPs result in no change in membrane
potential by opening Chloride channels that
stabilize membrane potential at resting value
(Nernst Potential for Cl- -70mV) or in cells
that actively transport Cl- out.
EK
6
Figure 6.33
Size of PSP is Variable!
S 4
Who Cares?
Presynaptic Facilitation Presynaptic Inhibition
Mechanism vary Ca entry in presynaptic
terminal B.
7
Figure 6.31
S 5
Summation and Synaptic Integration
Different times
Different locations
Challenge question Suppose each IPSP
hyperpolarizes by 5 mV and each EPSP depolarizes
by 5 mV. If 4 inhibitory synapses are active at
the same time, how many excitatory synapses must
be active simultaneously to exceed threshold (-55
mV) if the resting membrane potential is -70mV?
8
S 6
Synapses cover the dendrites and cell bodyof
CNS Neurons
What could be conjugated with a red fluorescent
marker to reveal synapses?
What is gray matter? What is white matter?
9
Figure 6.24
S 7
Section C Synapses and Synaptic Transmission
10
S 8
Synapses named for NT used -ergic Examples Ch
olinergic Adrenergic Serotonergic GABAergic Peptid
ergic
11
S 9
Pharmacological agents intended to act in brain
must be able to cross blood-brain barrier.
Treatments for Parkinsonism a) tablets of
L-Dopa (which crosses the BBB) unlike Dopamine
(which would have widespread effects)b) neuronal
transplants (self, fetal, stem cell, pig), c)
electrical stimulation NIH Stem Cell Information
Who Cares?
Parkinsons Disease