front 1 3 jobs of the nervous systems | back 1 1. Gather sensory information both internal and external
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front 2 central nervous system (CNS) | back 2 brain and spinal cord |
front 3 Peripheral Nervous System (PNS) | back 3 - nerves not located in the CNS
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front 4 Afferent | back 4 To CNS
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front 5 Efferent | back 5 From CNS
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front 6 Nervous Tissue in PNS and CNS is made of: | back 6 1. Nerve cells (neurons) - information messengers. Most diverse kind of cells in body
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front 7 Neuroglia of CNS | back 7 1. Astrocytes
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front 8 Astrocytes | back 8 - most abundant glial cells
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front 9 3 jobs of astrocytes | back 9 1. help form a network on which neurons grow
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front 10 Microglia | back 10 - protective role
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front 11 Ependymal Cells | back 11 - line cavities of brain and spinal cord
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front 12 Oligodendrocytes | back 12 - wrap their branches around large nerve fibers (axons) and create an insulating cover or Myelin Sheath - for up to 60 axons |
front 13 Neuroglia of the PNS | back 13 1. Satellite Cells
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front 14 Satellite Cells | back 14 - function unknown
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front 15 Schwann Cells | back 15 - wrap around large nerves to create a Myelin Sheath
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front 16 Neurons | back 16 Cells of nervous systems are neurons
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front 17 Structure of Neurons | back 17 - many different shapes
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front 18 Cell body of neuron | back 18 also called the Soma
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front 19 Nuclei | back 19 a cluster of cell bodies in the CNS |
front 20 Ganglia | back 20 a cluster of cell bodies in the PNS |
front 21 Dendrites | back 21 - branching extensions of the cell body
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front 22 Axon | back 22 - one per neuron
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front 23 axolemma | back 23 plasma membrane of axon |
front 24 Anterograde | back 24 From cell body to terminal
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front 25 Retrograde | back 25 To cell body from terminal
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front 26 Myelin Sheath | back 26 - large, long axons are covered in Myelin (fatty protein) that electrically insulates axons
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front 27 Node of Ranvier | back 27 a gap left between adjacent Schwann cells
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front 28 white matter | back 28 myelinated fibers |
front 29 gray matter | back 29 unmyelinated fibers and cell bodies |
front 30 Structural Classification of Neurons | back 30 1. Multipolar
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front 31 Multipolar | back 31 - 99% of neurons
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front 32 Bipolar | back 32 have 2 processes (axon and dendrite)
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front 33 Unipolar | back 33 - 1 process emerges from cell body
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front 34 Nerve Impulses | back 34 - neurons communicate with each other by generating nerve impulses
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front 35 Graded Response | back 35 a short lived, local change in membrane potential (depolarization). This change causes current to flow that decreases in strength with distance |
front 36 Action Potential | back 36 a large, short depolarization event that does NOT decrease in strength with distance. They occur only in axons, sarcolemma and T-tubules |
front 37 Why the difference between AP and GR? | back 37 1. the dendrites and cell body have chemical and/or mechanical gated ion channels
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front 38 How do you get electrical current to flow? | back 38 First, all plasma membranes must be polarized at rest.
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front 39 Why is there a voltage difference between the inside of the membrane and the outside? | back 39 - Because there are leaky ion channels sprinkled all over the membrane of the neuron
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front 40 Leaky Ion Channel | back 40 allows K+ to leak out of the cell easier than Na+ can leak back into the cell |
front 41 Sodium/Potassium pump | back 41 pumps out 3 positive ions (Na+) for every 2 it pumps in (K+) |
front 42 The net effect is; | back 42 more positive charges collect on the outside surface of the cell membrane than the inside surface creating a voltage difference of -70mV, called the Resting Membrane Potential |
front 43 Resting Membrane Potential | back 43 Inside cell is more negative than outside (-70mv)
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front 44 So what is depolarization? | back 44 - a change in Resting Membrane Potential such that the inside now becomes more positive than it was when at rest |
front 45 Signal Conduction along nerves | back 45 - information is carried by nerves in the form of electrical current |
front 46 2 forms of electrical signals | back 46 1. graded respons
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front 47 graded response (detail) | back 47 - occur at sensory receptor endings and dendrites
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front 48 Mechanism of a graded response | back 48 1. A small region of membrane becomes depolarized
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front 49 action potential (detail) | back 49 - generated by excitable tissue i.e. nerves and muscle cells
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front 50 profile of the voltage changes | back 50 1. RMP ~ -70mv
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front 51 Ionic Basis of action potentials | back 51 1. RMP generated by Na+/K+ pump. Deficit of the positive ions inside cell. RMP ~ -70mv. Na+ and K+ channels closed
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front 52 _________ restores resting electrical conditions but _______________ are returned by 'reving' up Na+/K+ pump | back 52 Repolarization; ionic distributions |
front 53 Refractory period | back 53 from the opening of the Na+ channels to the resetting of the Na+ channels. The neuron cannot respond to another stimulus while in this phase |
front 54 Propagation of an action potential | back 54 - action potentials are propagated (transmitted) along the entire length of the axon
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front 55 Speed of Nerve Impulses | back 55 - skeletal muscle - faster in nerves
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front 56 Speed of conduction is determined by: | back 56 1. axon diameter
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front 57 axon diameter | back 57 larger diameter axon means less resistance to flow of ions which means membrane reaches threshold faster and impulses travel faster |
front 58 Myelination | back 58 in unmyelinated nerves AP's are generated next to each other - one after another - continuous conduction
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front 59 Classification of Nerve fibers (axons) | back 59 1. group A
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front 60 Group A | back 60 mostly sensory and motor fibers serving:
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front 61 Group B | back 61 Autonomic Nervous system sensory and motor fibers
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front 62 Group C | back 62 Same fibers as group B
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front 63 Pathologies of the Nervous System | back 63 1. Multiple Sclerosis
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front 64 Multiple Sclerosis | back 64 - an autoimmune disease
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front 65 Amyotrophic Lateral Sclerosis (ALS) | back 65 - Lou-Gehrig's Disease
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front 66 Electrical to chemical signaling | back 66 - nerve impulses travel along Motor Neurons
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front 67 Nerve Terminal | back 67 - contains synaptic vesicles (sacs containing neurotransmitter).
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front 68 Synaptic Cleft | back 68 - is a gap between nerve terminal and sarcolemma |
front 69 Motor End Plate | back 69 A dimple in the sarcolemma
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front 70 Mechanism of Nerve Terminal | back 70 1. Nerve impulse travels down axon
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front 71 How is signal terminated? | back 71 1. decrease nerve impulses
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front 72 Pathologies | back 72 Myasthenia Gravis
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front 73 Tubocurarine (curare) | back 73 Botanical agent from S. America
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front 74 Anticholinesterases | back 74 drugs that inhibit (block) acetylcholinesterase (AchE)
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front 75 Medicinal Uses | back 75 to increase tone in smooth muscle of GI tract and bladder
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front 76 tetrodotoxin | back 76 - one of the most potent poisions known
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front 77 Botulinus Toxin | back 77 BOTOX
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front 78 Local Anesthetics | back 78 - procaine, lidocaine, cocaine
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front 79 Synapses and Neurotransmitters | back 79 - synapses release and receive NT's
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front 80 A synaps has 2 parts: | back 80 1. Nerve terminal - contains synaptic vesicles that fuse with presynaptic membrane to exocytose NT's into synaptic cleft
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front 81 Excitatory Synapses | back 81 - NT release causes depolarization or postsynaptic membrane
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front 82 Inhibitory Synapses | back 82 - NT release induces hyperpolarization of postynaptic membrane
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front 83 Neurotransmitters | back 83 to date there are over 50 NT's
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front 84 Classification of NT's | back 84 NT's are classified based on chemical structure
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front 85 Acetylcholine (Ach) | back 85 - released at NMJ - excitatory
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front 86 Biogenic Amines | back 86 Dopamine, norepinephrine, epinephrine (adrenalin), serotonin, histamine |
front 87 Amino Acids | back 87 Inhibitory - Gamm AMinobutyric Acid (GABA)
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front 88 Smooth Muscle | back 88 found in the walls of hollow organs (except the heart) |
front 89 Smooth muscle cells | back 89 - spindle shaped
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front 90 arrangement of muscle cells | back 90 - two sheets of smooth muscle found in most organs
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front 91 longitudinal layer | back 91 - one sheet runs parallel to long axis or organ
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front 92 circular layer | back 92 - fibers run around circumference of organ
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front 93 Peristalsis | back 93 alternating contraction/relaxation of muscle sheets |
front 94 Also contractions occur in: | back 94 Bladder
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front 95 Main characteristics of smooth muscle | back 95 no NMJ
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front 96 The Brain | back 96 Adult Brain Regions - named from embryological development
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front 97 Neural Tube | back 97 Anterior (rostral)
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front 98 Primary Brain vesicles | back 98 forebrain
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front 99 Secondary Brain Vesicles | back 99 Telencephalon
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front 100 Adult brain structures | back 100 Telencephalon - Cerebrum: cerebral hemispheres (cortex, white matter, basal nuclei)
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front 101 Adult Neural Canal Regions | back 101 Telencephalon - lateral ventricles
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front 102 General Organization of the brain | back 102 1. Outer layer (cortex) - Gray matter (neuronal cell bodies)
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front 103 Ventricles | back 103 Are hollow chambers filled with cerebrospinal fluid (CSF)
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