Exam Ii - Anatomy Physiology

Front 1

Basic functions of the nervous system

Back 1

Sensory Input - monitoring stimuli
Integration - interpretation of sensory input
Motor output - response to stimuli

Front 2

Division of the Nervous system

Back 2

Central Nervous System (CNS)
Peripheral Nervous System (PNS)

Front 3

Central Nervous System consists of

Back 3

Brain and spinal cord

Front 4

Peripheral Nervous System consists of

Back 4

Paired spinal and cranial nerves

Front 5

What is the difference between CNS and PNS?

Back 5

CNS is the integration and command center. PNS carries the messages to and from the spinal cord and brain.

Front 6

Functional divisions of PNS

Back 6

Sensory (afferent = up) division
Motor (efferent = out) division

Front 7

Sensory division of the PNS contains

Back 7

Somatic afferent fibers - carry impulses from skin, skeletal muscles, and joints to the brain.
Visceral afferent fibers - transmits impulses from visceral organs to the brain

Front 8

Motor division of the PNS contains

Back 8

Somatic nervous system - conscious control of skeletal muscles
Autonomic nervous system - regulates smooth muscles, cardiac muscles (sympathetic - activated when stressed) (parasympathetic - when you are relaxed)

Front 9

Neuroglia (glial cells)

Back 9

provide supportive scaffolding for neurons
Segregates and insulates nerves
There are 6 types - 4 in CNS, 2 in PNS

Front 10

Astrocytes

Back 10

Most abundant/versatile glial cells
Anchor neurons to their nutrient supplies
Control the chemical environment - remove leaked Potassium
(support and clean up)

Front 11

Micoglia

Back 11

A type of glial cells - monitor the health of nearby neurons. Cells of the immune system are denied access to the CNS
Prevent body from attacking the brain

Front 12

Ependymal

Back 12

Line the central cavities of the brain and spinal column forming a fairly impermeable barrier between spinal fluid and tissue fluid bathing the cells of the CNS

Front 13

Oligodendrocytes

Back 13

Branched cells that wrap CNS nerve fibers - form myelin sheaths

Front 14

Schwann Cells

Back 14

Same as oligodendrocytes but are in the PNS. Surround fibers forming the myelin sheaths

Front 15

Neurons

Back 15

Structural unit of the nervous system. Composed of a body, axon, and dendrites. Long lived and amitotic (cannot divide)

Front 16

Nerve Cell Body

Back 16

aka Perikaryon or Soma
Has no centrioles (hence it's amitotic)
Clusters of cell bodies in the CNS are called nuclei, and in the PNS are called ganglia

Front 17

Nissl body

Back 17

Cell body's protein, ribosomes

Front 18

Dendrites

Back 18

Process of motor neurons, short. Input regions of the neuron

Front 19

Axons

Back 19

Slender process of uniform diameter arising from the hillock

Front 20

Function of axons

Back 20

Movement towards axonal terminal - anterograde
Movement away from axonal terminal - retrograde

Front 21

Myelin Sheath

Back 21

Whitish, fatty, segmented sheath around most long axons

Front 22

Function of myelin sheath

Back 22

Increase the speed of nerve impulse transmission

Front 23

Nodes of Ranvier

Back 23

Gaps in the myelin sheath between adjacent Schwann cells

Front 24

Myelinated fibers vs Unmyelinated fibers

Back 24

Myelinated fibers conduct nerve impulses rapidly.
Unmyelinated fibers conduct impulses slowly. Dendrites are always unmyelinated.

Front 25

White matter vs Gray matter

Back 25

White Matter - dense collections of myelinated fibers (axons)
Gray Matter - mostly soma and umyelinated fibers

Front 26

Depolarization

Back 26

the inside of the membrane becomes less negative because sodium ions are going in

Front 27

Repolarization

Back 27

the membrane returns to its resting membrane potential

Front 28

Hyperpolarization

Back 28

the inside of the membrane becomes more negative than the resting potential. Na gates are open

Front 29

Threshold

Back 29

a critical level of depolarization (-55 - -50 mV). Depolarization becomes self generating

Front 30

Polarized state

Back 30

Inside of the membrane is relatively negative in comparison to the outside; resting state

Front 31

What substance acts as a chemical transmitter at a synapse or neuron junction?

Back 31

Neurotransmitter

Front 32

Define neurotransmitter

Back 32

Chemicals used for neuronal communication with the body and the brain

Front 33

Name two common neurotransmitters

Back 33

Acetylcholine (ACh)
Biogenic Amines

Front 34

Acetylcholine

Back 34

Relased at the neuromuscular junction
Degraded by the enzyme acetylcholinesterase

Front 35

Biogenic Amines

Back 35

Include - dopamine, norepinephrine, and epinephrine
Plays role in emotional behaviors and biological clock

Front 36

How are neurotransmitters classified?

Back 36

Chemically and functionally

Front 37

Temporal Summation

Back 37

Presynaptic neurons transmit impulses in rapid-fire order. Timewise

Front 38

Spatial summation

Back 38

Postsynaptic neuron is stimulated by a large number of terminals at the same time by the same or different neuron.

Front 39

Synaptic Potential

Back 39

Repeated or continuous use of a synapse which enhances the presynaptic neuron's ability to excite the postsynaptic neuron, producing larger-than-expected postsynaptic potentials

Front 40

Presynaptic Inhibition

Back 40

Opposite of synaptic potential
Release of an excitatory neurotransmitter by one neuron is inhibited by the activity of another neuron via an axoaxonic synapse
As a results, less neurotransmitter is released and bound, a smaller EPSP

Front 41

Postsynaptic Potential

Back 41

Neurotransmitter receptors create change in the membrane potential according to:
-amount of neurotransmitter released
-Amount of time the neurotransmitter is bound to the receptor

Front 42

Types of postsynaptic potentials:

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EPSP - excitatoory postsynaptic potential
IPSP - inhibitory postsynaptic potential

Front 43

EPSP's

Back 43

graded potentials that can initiate an action potential in axon.
Use only chemically gated channels

Front 44

IPSP's

Back 44

Bind to receptor at inhibitory synapses
Reduces the postsynaptic neuron's ability to produce an action potential

Front 45

Resting membrane potential

Back 45

-70mV
Generated by different conc of Na, K, Cl, and protein anions
Consequence of sodium-potassium pump

Front 46

Graded Potentials

Back 46

Short-lived, local changes in membrane potential
Intensity decreases w/distance
Magnitude directly related to stimulus
Can initiate action potentials

Front 47

Stages of Action Potential

Back 47

1. Resting State
2. Depolarization
3. Repolarization
4. Hyperpolarization

Front 48

Depolarization phase

Back 48

Sodium permeability increases
Na gates open / K gates close
At threshold, it becomes self-generating

Front 49

Repolarization phase

Back 49

Sodium inactivation gates close
Sodium permeability declines to resting levels
Voltage sensitive K gates open

Front 50

Hyperpolarization Phase

Back 50

Potassium gates remain open, causing an excessive efflux of K

Front 51

Microglia Cells

Back 51

Small, ovoid cells with spiny pricesses
Phagocytes that monitor the health of neurons

Front 52

Ependymal Cells

Back 52

Range in shape from squamous to columnar
Line the central cavities of the brain and spinal column forming a fairly permeable barrier between the cerebrospinal fluid

Front 53

Oligodendrocytes

Back 53

Branched cells that wrap CNS nerve fibers
Form myelin sheaths in the CNS

Front 54

Schwann Cells

Back 54

Form myelin sheaths in the PNS

Front 55

Myelin sheath

Back 55

Whitish fatty, segmented sheath around most long axons
Increases the speed of nerve impulse transmission

Front 56

How are myelin sheaths formed?

Back 56

schwann cells envelopes an axon
encloses the axon with its plasma membrane and wraps around axon

Front 57

Nodes of Ranvier

Back 57

Gaps in the myelin sheath between adjacent schwann cells

Front 58

Structural Classification of Neurons

Back 58

Body
Axon
Dendrites
Live long, amitotic

Front 59

Functional Classification of Neurons

Back 59

Electrical signaling
Cell-to-cell signaling during development

Front 60

Afferent vs Efferent

Back 60

Transmits impulses toward the CNS
Carries impulses away from the CNs

Front 61

Absolute Refractory Period

Back 61

Nerve cell cannot reply to another stimulus regardless of strength.
Period of depolarization.
Ensures each action potential is separate
Enforces on-way transmission of nerve impulses

Front 62

Relative Refractory Period

Back 62

Follows absolute refractory period
Can acknowledge another stimulus only if greater in strength
Sodium gates closed, potassium gates opened, repolarization (all at the same time)

Front 63

Saltatory Conduction

Back 63

Current passes through myelinated axon only at the nodes of Ranvier
Voltage gated Na channels are conc at nodes
Action potential jumps from one node to the next
Much faster than unmeylinated

Front 64

Synapse

Back 64

A junction that mediates information transfer from on neuron to another, or an effector cell

Front 65

Axosomatic synapse

Back 65

Synapse between the axon of one neuron and the soma of another

Front 66

Axodendtric Synapse

Back 66

synapse between the axon of one neuron and the dendrite of another

Front 67

Electrical Synapse

Back 67

Important in the CNS
arousal from sleep, mental attention, emotions and memory

Front 68

Chemical Synapse

Back 68

Specialized for the release and reception of neurotransmitters

Front 69

Excitatory Postsynaptic Potential

Back 69

Potentials that can initiate an action potential in axon
Uses only chemically gated channels

Front 70

Inhibitory Synapses

Back 70

Neurotransmitter binding to a receptor
Reduces the postsynaptic neuron's ability to produce an action potential

Front 71

Multiple sclerosis

Back 71

Autoimmune disease
Nerve fibers are severed and myelin sheaths in CNS become nonfunctional scleroses
Shot-circuiting of nerve impulses occurs

Front 72

Symptons of MS

Back 72

visual disturbance, weakness, loss of muscular control and urinary control

Front 73

Convergent Neuronal Pools

Back 73

Multiple incoming fibers stimulate a single fiber. Resulting in either strong stimulation or inhibition

Front 74

Divergent Neuronal Pools

Back 74

One incoming fiber stimulates every increasing number of fibers, often amplifying circuits

Front 75

Reverberating Neuronal Pools

Back 75

Chain of neurons containing collateral synapses with previous neruons in the chain

Front 76

Parallel after-discharge Neuronal Pools

Back 76

Incoming neurons stimulate several neurons in parallel arrays

Front 77

Serial Processing

Back 77

Input travels along one pathway to a specific destination
Example: spinal reflexes

Front 78

Parallel Processing

Back 78

Input travels along several pathways
One stimulus promotes numerous responses

Front 79

Basal Nuclei

Back 79

Masses of gray matter found deep within the coritcal white matter

Front 80

Function of Basal Nuclei

Back 80

Influence muscular activity
Regulate attention and cognition
Inhibit unnecessary movements

Front 81

Disease of the Basal Nuclei

Back 81

Parkinson and Huntington's

Front 82

Diencephalon

Back 82

Consists of - Thalamus, hypothalamus, and epithalamus
Encloses the third ventricle
Forms the central core of the forebrain

Front 83

Hypothalamus

Back 83

Located below the thalamus
Relay station for olfactory pathways
Infundibulum - connects the the pituitary gland

Front 84

Function of Hypothalamus

Back 84

Autonomic control center - regulates everything automatic in the body
Emotions, hunger, sleep, digestion, etc

Front 85

Major regions of the Brain Stem

Back 85

Midbrain, pons, and medulla oblongata

Front 86

Function of midbrain

Back 86

Controls cranial nerves III (oculomotor) and IV (trochlear)
Visual reflex center, coordinates head and eye movement
Auditory relay center

Front 87

Function of Pons

Back 87

Relay impulses between motor cortex and cerebellum
Origin of cranial nerve V (trigeminal), VI (abducens), and VII (facial)

Front 88

Function of Medulla Oblongata

Back 88

Allows the right side of the brain to control the left side of the body. Pyramids

Front 89

Structure of cerebellum

Back 89

Two symmetrical hemispheres contain three lobes
Arbor vitae - distinctive treelike pattern of the cerebellar white matter

Front 90

Function of the cerebellum

Back 90

Receives impulses of the intent to initiate voluntary movement
Calculates best way to preform a movement
Language and problem solving

Front 91

Limbic system location

Back 91

medial aspects of cerebral hemispheres and diencephalon

Front 92

Function of Limbic system

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Amygdala - anger, danger, fear
Cingulate gyrus - expressing emotions (gestures), solves mental conflict
Associates smells with emotions

Front 93

Reticular system location

Back 93

Extends through the core of the medulla oblongata, pons, and midbrain

Front 94

Function of reticular system

Back 94

Keeps cerebral cortex alert
Filters weak/repetitive stimuli
Motor movements

Front 95

EEG

Back 95

Electroencephalogram - records brain activity

Front 96

Alpha waves

Back 96

Regular and rhythmic, low amplitude, slow, synchronous waves indicating an idling brain

Front 97

Beta waves

Back 97

rythmic, more irregular waves occuring during the awake and mentally alert state

Front 98

Theta waves

Back 98

more irregular than alpha, common in children but abnormal in adults

Front 99

Delta waves

Back 99

high-amplitude waves seen in dep sleep and when reticular activating system is damped

Front 100

REM

Back 100

Vital signs increase
Skeletal muscles inhibited
most dreaming

Front 101

NREM

Back 101

4 stages -
1 .alpha waves, easily arroused
2. arousal more difficult
3. sleep deepens, theta and delta
4. delta wave dominate

Front 102

The fourth ventricle is located in the

Back 102

Medulla oblongata, brainstem, and pons

Front 103

The cerebral aqueduct is located in the

Back 103

Brain stem

Front 104

The third ventricle is located in the

Back 104

Thalamus (hypo/epi)

Front 105

The lateral ventricle is located in the

Back 105

Cerebrum

Front 106

The forebrain consists of - and -.

Back 106

Telencephalon and Diencephalon

Front 107

The Midbrain consists of the -

Back 107

Mesencephalon

Front 108

The hindbrain consist of the - and -

Back 108

Metencephalon and Myelencephalon

Front 109

The cerebrum is located in the

Back 109

telencephaalon

Front 110

The Thalamus is located in the

Back 110

Diencephalon

Front 111

The brain stem is located in the

Back 111

Mesencephalon

Front 112

The medulla oblongata is located in the

Back 112

Myelencephalon

Front 113

The _____ seprates the cerebral hemispheres

Back 113

Longitudinal fissure

Front 114

The ______ separates the frontal and parietal lobes.

Back 114

Central sulcus

Front 115

______ is located usually in the left hemisphere, and controls motor speech.

Back 115

Broca's Area

Front 116

______ enter the himsphere from lower brain or cord centers

Back 116

Projection fibers

Front 117

______ connect corresponding gray areas of the two hemispheres

Back 117

Association fibers

Front 118

______ connect corresponding gray areas of the two hemispheres.

Back 118

Comissures

Front 119

Ohm's Law

Back 119

Current = voltage / resistance

Front 120

Clusters of cell bodies in the CNS are called _____ and _____ lie along the nerves in the PNS.

Back 120

nuclei
ganglia

Front 121

Ca channels _____ when nerve impulses reach the axonal terminal of the presynaptic neuron.

Back 121

opens

Front 122

Degeneration of _____ ______ is the ultimate cause of Parkinson's disease.

Back 122

substantia nigra

Front 123

______ _______ is a watery solution similar in composition to blood plasma.

Back 123

Cerebrospinal fluid

Front 124

Dura mater, arachnoid mater, and pia mater are all ______, connective tissue membrane.

Back 124

Meninges

Front 125

Meninges ______ the CNS and contain ______ _______.

Back 125

protect
Cerebrospinal fluid

Front 126

_____ mater is a butterfly shape in the center of the spine. _____ lines the circumfrence.

Back 126

Gray
White

Front 127

__ # of ____ are pumped out and __ # of ____ are pumped in the cell.

Back 127

3 Na
2 K