**a&p 2 Chap 12

Front 1

Ganglia

Back 1

Small masses of nervous tissue located outside brain and spinal cord but are closely associated with cranial and spinal nerves

Front 2

Sensory Receptors

Back 2

Dentrites of sensory neurons

Front 3

Afferent Neurons

Back 3

aka Sensory Neurons that carry stimuli into the brain and spinal cord

Front 4

Vast majority of neurons in the body that participate in integration

Back 4

Interneurons

Front 5

Efferent Neurons

Back 5

aka Motor neurons that carry information from the brain to spinal cord or to effectors

Front 6

Two main subdivisions of the nervous system and their parts

Back 6

CNS - Brain & Spinal Cord

PNS - Cranial & Spinal nerves, ganglia and sensory receptors

Front 7

Divisions of the PNS

Back 7

Somatic

Autonomic

Enteric

Front 8

SNS and its two constituents

Back 8

Composed of
1) Sensory neurons that convey info from somatic receptors to the CNS

2) Motor neurons that conduct impulses from CNS to Skeletal Muscles Only

Front 9

ANS and its two constituents

Back 9

Composed of:
1) Sensory neurons that convey info from autonomic receptors in lungs, stomach etc

2) Motor neurons that convey info from CNS to smooth and cardiac muscle and glands

Front 10

Two Branches of the Motor part of ANS

Back 10

Composed of:
1) Sympathetic - Regulates Fight or Flight

2) Parasympathetic - Regulates Rest and Digest

Front 11

Brain of the Gut which can operate somewhat independent of the ANS and CNS

Back 11

ENS

Front 12

Stimulus

Back 12

Any change in the enviornment that is strong enough to initiate an action potential

Front 13

Perikaryon

Back 13

Neuron Cell Body

Front 14

Nissl Bodies

Back 14

Clusters of Rough ER which are sites of protein synthesis in Neurons

Front 15

Brownish clumps of pigments that accumulates in aging neurons but doesn't really harm it

Back 15

Lipofuscin

Front 16

Dendrites

Back 16

Receiving portions of a neuron that form tree-shaped processes extending from cell body

Front 17

Synapse

Back 17

Site of communication between two neurons or a neuron and an effector

Front 18

Swollen Bulb shaped structures at the end of axon terminals

Back 18

Synaptic End Bulbs

Front 19

Slow Axonal Transport

Back 19

Conveys new Axoplasm in one direction toward developing or regenerating axon terminals only

1-5mm per day

Front 20

Fast Axonal Transport

Back 20

Moves material 200 - 400mm per day and uses proteins to move materials in both directions along microtubule surfaces

Front 21

Multipolar Neuron

Back 21

Type that has several dendrites and one axon

Composes most of neurons in Brain and Spinal Cord

Front 22

Bipolar Neuron

Back 22

Type that has one main dendrite and one axon

Found in Retina, inner ear, and olfactory area of brain

Front 23

Unipolar Neuron

Back 23

Type that ended up with a fused axon and dendrite during development

Used for sensory purposes, PNS end has dendrites and CNS end has synaptic end bulbs

Front 24

Neuroglia of the CNS

Back 24

Astrocyte
Oligodendrocyte
Ependymal Cell
Microglia

Front 25

Neuroglia of the PNS

Back 25

Schwann Cells & Satellite cells

Front 26

Astrocyte & it's 5 functions

Back 26

Largest and most numerous of the Neuroglia

1) Contains microfilaments for support
2) Their processes wrap around capillaries to form the BBB
3) Promotes embryonic growth of neurons
4) Maintains appropriate chemical environment
5) Helps memory by promoting formation of neural synapses

Front 27

Oligodendrocytes

Back 27

Smaller resemblances of astrocytes containing fewer processes and provides myelin sheath

Front 28

Microglia

Back 28

Small cells with slender processes that function as phagocytes of the nervous system

Front 29

Ependymal Cells

Back 29

Cuboidal to columnar shaped cells that possess microvilli and cilia & assists in circulation of cerebral spinal fluid

Front 30

Schwann Cells

Back 30

Cells that can myelinate one axon or contain as many as 20 unmyelinated axons. Also participates in axon regeneration

Front 31

Satellite Cells

Back 31

Cells that surround cell bodies of PNS neurons. Provies support and regulates exchange of materials between cell body and interstitial fluid

Front 32

Nodes of Ranvier

Back 32

Gaps in myelin sheath

Front 33

White Matter

Back 33

Part of CNS composed primarily of Myelinated Axons which gives its color

Front 34

Gray Matter

Back 34

Part of CNS that gets its color from gray Nissl Bodies and contains little to no myelin

Front 35

Threshold

Back 35

The level of AP where the All or nothing principle takes place

About -55 mV in many neurons

Front 36

Salatory Conduction

Back 36

Jumping conduction of Myelinated Neurons between Nodes of Ranviers

Front 37

Axodendritic Synapse

Back 37

Synapse between Axon and Dendrite

Front 38

Axosomatic Synapse

Back 38

Synapse between Axon and Cell Body

Front 39

Axoaxonic Synapse

Back 39

Synapse between Axon and Axon

Front 40

Summation

Back 40

Integration of inputs received from the thousands of synapses in a neuron

Front 41

Spatial Summation

Back 41

When summation results from build up of neurotrasmitters by several presynaptic bulbs

Front 42

Temporal Summation

Back 42

When summation results from neurotransmitters released in rapid successions by a single presynaptic bulb

Front 43

Amino Acids with strong exitatory effects

Back 43

Aspartate & Glutamate

Front 44

Amino Acids with Strong Inhibitory effects

Back 44

GABA - GamaAminoButyric Acid & Glycine

Front 45

Excitotoxicity

Back 45

Destruction of Neurons through prolonged stimulation

Front 46

Two enzymes that break down Catecholamines

Back 46

COMT & MAO

Catechol O Methyl Transferase
Monoamine Oxidase

Front 47

Nitric Oxide

Back 47

Important Neurotransmitter that is produced only upon demand and diffuses across lipid membrane

Front 48

NOS

Back 48

Synthesizes NO

Front 49

Neuropeptides

Back 49

Neurotransmitters consisting of 3 to 40 amino acids linked by peptide bonds

Front 50

Enkephalins

Back 50

Natural Anasthetic 200 times more potent than morphine

Works by blocking effects of Substance P

Front 51

Endorphins & Dynorphines

Back 51

Through to be the body's natural painkillers

Front 52

Substance P

Back 52

A neuropeptide released by neurons to transmit pain related input to the CNS

Front 53

Single presynaptic Neuron stimulates increasing numbers of cells along the circuit

Back 53

Diverging Circuit

Front 54

Several Presynaptic Neurons gather together to stimulate a single postsynaptic neuron

Back 54

Converging Circuit

Front 55

Circuit of neurons that causes postsynaptic neuron to transmit a series of nerve impulses and some even back to the presynaptic neuron

Back 55

Reverberating Circuit

Front 56

Single presynaptic cell stimulates group of neurons and then each synapses with a common postsynaptic cell to initiate temporal summation

Back 56

Parallel After-Discharge Circuit

Front 57

Chromatolysis

Back 57

Process where Nissl Bodies break up into fine granular masses after an injury

Front 58

Wallerian Degeneration

Back 58

Process during the 3rd to 5th day where the distal portion of axon and myelin sheath degenerates for the repair process

Front 59

Leakage Channels

Back 59

Gated Channels that randomly alternate between open and closed positions

More of the K+ ones exist than Na+ ones

Front 60

Voltage Gated Channels

Back 60

Gated channel that opens in response to a change in membrane potential

-Participates in generation & conduction of action potential

Front 61

Ligand Gated Channel

Back 61

Gated channel that opens in response to specific chemical stimulus

Front 62

Mechanically Gated Channel

Back 62

Gated channels that opens in response to a mechanical stimulation

Front 63

Total Membrane potential in a typical Neuron

Back 63

-70mV

Front 64

Absolute Refractory Period

Back 64

0.4msec in large diameter axons and

4msec in small diameter axons

Period in which even a every strong stimulus cannot initiate a action potential since Na+ channels haven't returned to resting state

Front 65

Relative Refractory Period

Back 65

Period in which only a larger than normal stimulus can initiate an AP because K+ channels are still open even though Na+ channels have already returned to resting state

Front 66

Continuous Conduction

Back 66

Normal Conduction in unmyelinated axons

Front 67

A,B, & C Fibers

Back 67

- All myelinated & large diameter
- All myelinated but smaller diameter
- Smallest & all unmyelinated

Front 68

Electrical Synapses

Back 68

Contains Gap Junctions that allows passing of ions

- Faster communication & Syncronization

Front 69

What triggers exocytosis at SEB

Back 69

Opening of Ca2+ channels at the end

Front 70

EPSP

Back 70

Brought about by opening of K+, Ca2+ & Na+ Ion channels

Na+ is greatest so this causes Depolarization

Front 71

IPSP

Back 71

Brough about by opening of K+ & Cl- ion channels

Cl- flows in & K+ flows out causing hyperpolarization

Front 72

Valium

Back 72

aka Diazepam

Enhances effects of GABA

Front 73

3 Catecholamines & Their functions

Back 73

Dopamine - Regulates muscle tone & responsible for pleasurable experiences

NE & Epinephrine - Regulates Mood, induction of awakening

Serotonin - Regulates temp, induction of sleep

Front 74

ATP & Other Purines

Back 74

Excitatory in both PNS & CNS and are often released with others such as ACh & NE

Front 75

Strychnine Poisoning

Back 75

Strychnine block Glycin receptors (Which inhibits) Causing massive contraction of skeletal muscles. Diaphragm can't relax - death

Front 76

Regeneration Tube

Back 76

Formed by Schwann cells across an injured area which guides growth of a new axon