1. End of Semester 2011 By Jamie, Gabby, Catherine, Samantha
The Nervous System
End of Semester 2011
By Jamie, Gabby, Catherine, Samantha

2. Organization of the NS

3. Function
Recognizes and coordinates the body’s response to changes in its internal and external environments

4. Nerves, Neurons, Neurons- cells that transmit impulses
-Sensory- carry impulses from sense organs to spinal cord and brain
Motor- carry impulses from the brain and the spinal cord to muscles and glands
Inter- connect sensory and motor neurons and carry impulses between them
Nerve- bundle of neurons (fibers)

5. Structure of a Neuron Cell Body -Nucleus -Cytoplasm
-Other common organelles
Dendrites
-Branch out extensively
-Receive impulses
Axon
Only 1 always
Conduct impulses AWAY from cell body
Encased by Schwann cells (make up myelin sheath)
Nodes of Ranvier
Axon Terminals
-Meet at synapse with dendrite of the next neuron
- Carry impulse to next neuron

7. Central NS
Made of-
Brain
Spinal Cord- contains interneurons

8. Peripheral NS Contains sensory and motor neurons Divided into:
Somatic NS- voluntary body movements
Autonomic NS-
--divided into: 1)sympathetic (speeding up-”flight or fight”)
2)parasymphathetic (slowing down- “rest and digest”)

9. Action Potential
What is it? – The transfer of an impulse from one neuron to the next
Vocab:
-Synapse – point of contact at which impulses are passed from one cell to another
-Neurotransmitters- tiny vesicles that travel across the synapse to bind with receptor proteins on the next neuron, relaying its message, or impulse

10. Action Potential
As an impulse travels along a neuron, a process of depolarizing and repolarizing the neuron occurs which allows the impulse to travel and be passed to the next neuron
1)Resting Potential- At resting potential, -70mv, the outside of the cell has more Na+; the inside has more K+. The outside is more + than the inside.(dna’s -2 charge from phosphate backbone)
2) Beginning of Depolarization- depolarization-inside becomes more positive than the outside. A stimulus triggers Na+ gates to open, some Na+ ions flow into cell. This causes a THRESHOLD to be reached (-55mv).X

11. 3) Depolarization- If the stimulus is strong enough to cause enough Na+ ions to come into the cell, THRESHOLD is reached (-55mv), and the impulse proceeds to travel. At this point, the inside is more + than the outside, with more Na+ on the inside and more K+ inside as well
4) Repolarization- Na+ reaches equilibrium after depolarization, and following this, K+ crosses the membrane to the outside of the cell through its K+channels; the inside of the cell becomes much more negative than the outside, with more K+ on the outside, and Na+ at equilibrium.
5) Refractory Period- Using an antiport (active transport) pump, which uses ATP, the Na+ is moved to the outside, and the K+ is moved to the inside in a ratio of 3:2, restoring the outside more+ than the inside, and more Na+ on the outside and more K+ on the inside.

13. Quiz What are the 3 types of neurons? sensory, external, and entry
Sensory, inter, and motor
Dendrites, axons, and nodes
Protection, integration, and response
2. ________ is a chemical substance used by one neuron to signal another.
Neuron messenger
Neuron signaler
Neurotransmitter
Signals
3. During repolarization, is the cell more or less positive on the inside?
Less positive
Same
More positive
None
4.During depolarization what kind of transport is used?
Anti port
No transport is used
Passive transport
Active transport
5. How do stimulants effect the body?
Increase energy/mood, decrease appitite
Decrease energy/mood, increase appitite
Decreases energy/mood decreases appitite
Increase energy/ mood, increases appitite

14. Quiz part 2 6) what do dendrites do? Receive impulses Give implulses
Pass on impulses
None of the above
7. What do depressents do to the body?
Speed up heart rate
Slow down heart rate, and Lower blood pressure
Make blood pressure higher
8. What is the threshold level? 55
100
-75
-55
9.What the parasympathetis division do?
Stays the same
Speeds up the body
Slows down the body
Both b and c
10. What is integration?
Multiple signals producing response
One signal producing a response
A response made by the brain
11. What happens during action potential?
Reverses charges from negative to positive
The electrical charge across the cell membrane of a neuron in its resting state
The neuron remains in its resting state
None of the above
12. What do neurotransmitters do?
Transfers an impulse to another cell
Chemical used by a neuron to transmit an impulse across a synapse to another cell
Carry impulses from an environment or from other neurons toward cell body
Releases amylase
13. Which of the following is not included in a neuron?
Synapse
Nodes
Nucleus
Axon terminals
14. What does the brain stem do?
Responsible for voluntary activity
Commands and moves muscles
Connects the brain and spinal cord
Controls hunger and thirst

15. 15. What are the steps to a reflex arc?
Detection- response- integration
Integration- detection- response
Response- integration- detection
Dection- integration- response
16. What is a snail like structure in the ear?
Bone
Cochlea
Inner ear tube
Tympanun
17. What is an example of a stimulant?
Amphetamine
Amylase
Morphine
Both a and b
What part of the body controls balance and posture?
a) Used to relieve pain
b) Used to increase alertness
c) Used to receive anxiety
d) None of the above
19. What part of the brain is used for learning?
Cerebrum
Cerebellum
Frontal lobe
20. A nerve cell that sends information throughout the body is _______?
Synapse
Neuron
axon

16. Answers!!!!!! B C A D