1. The Nervous system
The nerve cell is the basic unit of communication in the vertebrate nervous system

2. Components of the Nervous System
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Figure 11.1

3. Three Classes of neurons
The Neural circuit consists of
Sensory neurons
receptor for stimulus
Interneuron (CNS)
integrate signals
Motor neuron
transfer signal to effector (muscle)
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4. Types of Neurons in the Nervous System
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Figure 11.2

5. Anatomy of a Neuron Cell body: functional portion
Dendrites: short extensions that receive signals
Axon: long extension that transmits impulses
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6. Figure: 07-02a
Title:
The structure of a neuron.
Caption:

7. How does a neuron hold and move info?
A neuron at rest has a voltage difference across the plasma membrane called a resting voltage potential
An action potential (AP) is when this charge across the membrane is briefly switched
The action potential moves down the membrane at a rapid pace.
Ap can move faster over mylenated portions is called saltatory conduction
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8. Myelinated Neuron
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Figure 11.7a

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10. Maintenance of the Resting Membrane Potential
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Figure 11.3

11. Resting Membrane Potential, Graded Potentials, and an Action Potential
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Figure 11.4

12. Figure: 07-04
Title:
The plasma membrane of a neuron.
Caption:
The plasma membrane of a neuron contains two types of pathways through which ions can pass.

13. The Nerve Impulse Is a Bioelectrical Signal
The sodium-potassium pump uses ATP to transport sodium ions out and potassium ions in
The inside of a resting neuron has a negative charge relative to the outside
An action potential is a reversal and restoration of the charge difference across the membrane
The sodium-potassium pump restores the original distribution of ions
Action potentials are all-or-none events
A neuron cannot fire during the refractory period
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14. How does a signal move from one neuron to another?
A synaptic cleft divides 2 neurons
The AP will not move across the synaptic cleft
Neuro transmitters are released by the signal cell to the receiver cell
Move by diffusion
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16. Transfer of Information from Neuron to Target
Synaptic transmission:
Release of neurotransmitter: graded potential achieved
Effects of neurotransmitter:
Excitatory: depolarize postsynaptic cell
Inhibitory: hyperpolarize postsynaptic cell
Role of postsynaptic neuron: integrate and process information
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17. Types of chemical synapse
Acetylcholine: neuromuscular junctions, glands, brain and spinal cord
Norepinepherine: affects brain regions concerned with emotions, dreaming
From table 11.1
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18. Figure: 07-08
Title:
Synapses are interaction points within the nervous system.
Caption:
A neuron may have as many as 10,000 synapses. Some synapses have an excitatory effect on the membrane of the postsynaptic neuron and increase the likelihood that the neuron will fire. Other synapses have an inhibitory effect and reduce the likelihood that the postsynaptic neuron will fire. The net effect of all synapses will determine whether an action potential is generated in the postsynaptic neuron.

19. The nervous System
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20. Paths of information flow
Signals between the brain and spinal cord move to the body regions by nerves
Sensory nerves move a signal towards the brain and spinal cord
Motor neurons move a signal from the brain or spinal cord to the body
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21. Figure: 08-10
Title:
A reflex arc.
Caption:
A reflex arc consists of a sensory receptor, a sensory neuron, usually at least one interneuron, a motor neuron, and an effector.

22. Divisions of the nervous System
Central nervous system
CNS
Is the brain and spinal cord
Peripheral nervous system
PNS
all nerves that carry signals to and from the CNS
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23. Figure: 08-01
Title:
The nervous system.
Caption:
Although the human nervous system functions as an integrated whole, it is convenient to talk about its functional parts. The brain and spinal cord (shown in blue), form the central nervous system (CNS), which integrates incoming information and directs appropriate responses. Nerves carry information to and from the central nervous system. These nerves, together with collections of nerve cell bodies called ganglia, constitute the peripheral nervous system (PNS). The PNS may be divided into the somatic and the autonomic nervous systems. The somatic nervous system (shown in green) carries sensory information from the skin, skeletal muscles, and joints to the CNS and also directs our voluntary movements, such as those of the arms and legs. The autonomic nervous system (shown in pink) serves as an “automatic pilot" that regulates our involuntary bodily activities

24. Parts of the PNS
Sensory Division carries info to the brain and spinal cord.
Motor Division carries info from the brain to the bodies effectors (things that do the work)
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25. The Motor division of the PNS has 2 divisions
Somatic nerves relay commands to and from skeletal muscle
Voluntary control
Autonomic nerves send signals to and from smooth muscles
Involuntary control
Sympathetic
Parasympathetic
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26. The autonomic divisions
Parasympathetic
slow down the body activity when the body is not under stress
Rest and digest
Sympathetic
increase overall body activity during times of stress, excitement or danger
fight or flight response
hormone epinephrine
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27. Figure: 08-12
Title:
The structure and function of the autonomic nervous system.
Caption:
Most organs are innervated by fibers from both the sympathetic and the parasympathetic nervous systems. When this dual innervation occurs, the two branches of the autonomic nervous system have opposite effects on the level of activity of that organ. A chain of ganglia links the sympathetic nervous system. It usually acts as a unit, with all its effects occurring together. The ganglia of the parasympathetic nervous system are near the organ serviced. Its effects are more localized.
Fig 11.12

28. Sympathetic and Parasympathetic
Are Antagonistic
Work towards the automatic, subconscious maintenance of homeostasis.
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30. Parts of CNS Figure: 08-09ab Title: The spinal cord. Caption:
The spinal cord is a column of neural tissue that is protected by the bones of the vertebral column.

31. Components of the CNS Spinal cord Brain parts 31 pair of spinal nerves
Grey matter
White matter
Controls some reflex actions like bladder emptying
Brain parts
Hindbrain
medulla oblongata
cerebellum
pons
Midbrain
Forebrain
cerebrum
thalamus
hypothalamus
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32. Figure: 08-02
Title:
Protecting the central nervous system.
Caption:
The central nervous system is protected by the meninges, the cerebrospinal fluid, and the bones of the skull and vertebral column.

33. Ventricles of the Brain and Circulation of Cerebrospinal Fluid
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Figure 11.13

34. Brain: Major Divisions
Hindbrain: coordinates basic, automatic, vital functions
Medulla oblongata: controls automatic functions of internal organs
Cerebellum: coordinates basic movements
Pons: aids flow of information
Midbrain: coordinates muscles related to vision and hearing
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35. Brain: Processes and Acts on Information
Forebrain: receives and integrates information concerning emotions and conscious thought
Hypothalamus: helps regulate homeostasis
Thalamus: receiving, processing, and transfer center
Limbic system: neuronal pathways involved in emotions and memory
Cerebrum/cerebral cortex: higher functions
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36. Sleep Sleep center: reticular activating system (RAS)
Stages: based on electroencephalograms (EEGs):
Stage 1: transitional, random small waves on EEG
Stage 2: skeletal muscles relax, little eye or body movement, EEG shows sleep spindles
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37. Sleep (cont.)
Stage 3: heart and respiration slower, EEG shows slow wave sleep
Stage 4: difficult to awaken, heart and respiration slowest, body temperature decreased
REM (rapid eye movement) sleep: dreaming, EEG same as awake
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38. Limbic System: Emotions of Fear, Anger, Sorrow, Love
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Figure 11.19

39. Memory: Storing and Retrieving Information
Short term: working memory, information from previous few hours
Long term: information from previous days to years
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40. Other parts of the CNS
The two cerebral hemispheres communicate through the corpus collosum
left verbal skills
right nonverbal skills such as music math, abstract
Brain cavities and Canals
cerebrospinal fluid surrounds and fills in cavities in the brain
Blood Brain barrier- controls what moves into the brain. Will prevent infections.
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41. Our state of consciousness
The CNS governs sleeping, dozing, daydreaming and full alertness
neurons of the reticular activating system RAS control the changing levels of consciousness by releasing serotonin.
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42. Memory
Association is the linkage of information to structural and chemical changes
short term- few bits lasts a couple of hours
Long term- permanent and limitless
The most important info goes rapidly into long term storage
memory is stored in a form resistant to degradation
Possibly caused by changes in synapses.
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43. Tips on studying Concentrate on what you study. Minimize interference.
Study takes time.
Break material into smaller portions.
Rephrase materials in your own words.
Test yourself to see what you know.
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44. Primary somatosensory and motor areas of cerebral cortex
Figure: 08-07
Title:
Primary motor and primary somatosensory regions of the cerebral cortex.
Caption:
The primary motor and the primary somatosensory regions of the cerebral cortex are meticulously arranged, with each area corresponding to a particular part of the body. The general arrangement is similar in the two regions. However, the amount of sensory cortex devoted to each body part increases with the degree of sensitivity of that part. The largest portions of the cerebral motor cortex are devoted to the body parts over which we have the greatest degree of motor control.
Primary somatosensory and motor areas of cerebral cortex

45. Disorders of the nervous system
Trauma
Infections
Transmission and synaptic defects.
Abnormal growth
Headache
Tumors
Stroke
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46. Psychoactive Drugs Action: affects higher brain functions
Psychological dependence: user craves the feeling associated with the drug
Tolerance: takes more of the substance to achieve the same affect
Addiction: the need to continue obtaining and using a substance; no free choice
Withdrawal: physical symptoms that occur upon stopping the drug
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47. Know what the parts of the brain do
Brain parts
medulla oblongata
cerebellum
pons
cerebrum
thalamus
hypothalamus
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50. seratonin
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51. Just a reminder to talk about drugs that interact with brain.
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