Ans 205 Study Guide Exam (Nervous System)

Front 1

What are the functions of the nervous system?

Back 1

regulate mvt of body parts
regulate secretion from glands
collect info abt external/internal environment
maintaining a state of consciousness
stimulate behavior for survival

Front 2

__= network of billions of nerve cells linked together in a highly organized fashion to form the rapid control center of the body

Back 2

nervous system

Front 3

Similarities btw the nervous vs endocrine system?

Back 3

- they both monitor stimuli and react so as to maintain homeostasis

Front 4

Differences in the nervous vs endocrine system..

Back 4

- NS is a rapid, fast acting system whose effects do not always persevere
-the ES acts slower (via blood-borne chemical signals called hormones) and its actions are usually much longer lasting

Front 5

what are the 2 major divisions of the nervous system?

Back 5

central and peripheral nervous system

Front 6

There are 2 major cells types of the NS...

__= functional, signal conducting cells

__= supporting cells

Back 6

neurons

neuroglia

Front 7

__= cell body is soma
-one or more specialized. slender processes (axons/dendrites)
-an input region (dendrites/soma)
- a conducting component (axon)
-a secretory/output region ( axon terminal)

Back 7

neuron

Front 8

neurons can be __, __, __, ___

Back 8

bipolar , psuedounipolar, multipolar, unipolar

Front 9

__= junction btw an axon of one neuron with another neuron or another cell type

Back 9

synapse

Front 10

__= branches of the main axon

Back 10

axon collaterals

Front 11

__= white sheath of fatty material around nerve fibers (axons)- offers protection

Back 11

myelin

Front 12

__= many layers of cell membrane of glial cell wrapped around axon

Back 12

myelin sheath

Front 13

__= group of nerve cell bodies (soma) in CNS

Back 13

nuclei

Front 14

__= grp of nerve cell bodies in PNS

Back 14

ganglia

Front 15

__= bundle of nerve processes in CNS

Back 15

tracts/facsiculi

Front 16

__= bundle of nerve processes in PNS

Back 16

nerves

Front 17

___= aggregates of neuronal cell bodies

___= regions of tracts

Back 17

gray matter

white matter

Front 18

myelination in the CNS vs the PNS

Back 18

in the CNS- oligodendrocyte wraps around the axon

in the PNS- axon covered by myelin sheath (schwann cells)

Front 19

Glial cells of the NS
__= star shaped, abundant and versatile
- involved in the formation of the BBB

__= specialized immune cells that act as the macrophages of the CNS

Back 19

astrocytes


microglia

Front 20

glial cells of the NS..
__= low columnar epithelial-esque cells that line the ventricles of the brain and the central canal of the spinal cord, some are ciliated which facilitates the mvt of CSF

__= produce the myelin sheath which provides the electrical insulation for the neurons in the CNS

Back 20

ependymal cells

oligodendrocytes

Front 21

__= entanglement/meshwork
lined by ependymal cells

Back 21

choroid plexxus

Front 22

what are the major structures of the brain

Back 22

cerebrum
cerebellum
brain stem

Front 23

what are the structures of the brainstem?

Back 23

diencephalon
midbrain
pons
medulla oblongata

Front 24

__= characterized by Gyri(ridges) and sulci ( depressions/fissures)
-divides into left and right hemispheres
-lobes
-in cerebral cortex; neuronal cell bodies (gray matter) on exterior
-basal nucleus
-important in initiation and maintenance of normal motor activity

Back 24

cerebrum

Front 25

__= part of the brain with 2 laterla hemispheres
-median k/a vermis (resembles a worm)
-surface has many laminae/folia
-gray matter exterior/white central
Fxn: accurate timing /execution of mvts and coordinate muscle activity

Back 25

cerebellum

Front 26

What are the portions of the diencephalon?

Back 26

thalamus
hypothalamus
3rd ventricle

Front 27

parts of the diencephalon..
__= relay center for nerve fibers onnceting cerebrum to brainstem/cerebellum/spinal cord

__= ventral to the thalamus; ventral part attached to hypophysis (pituitary gland)

Back 27

thalamus

hypothalamus

Front 28

Portions of diencephalon..
__= it is a median cleft btw the 2 thalami, and is filled with CSF

Back 28

3rd ventricle

Front 29

___ gland produces melatonin (sleep/wake cycle) and is located in the epithalamus/above thalamus

Back 29

pineal

Front 30

What are the structures of the midbrain?

Back 30

peduncles
colliculi

Front 31

__= part of midbrain; a large bundle of nerves connecting spinal cord and brain stem to cerebral hemisphere; consists of descending motor fiber tracts

___= "little hills"; small bumps on dorsal side of the brain
-R/L rostral portions ( visual reflex)
-R/D caudal portions (relay nuclei for hearing)

Back 31

peduncle

colliculi

Front 32

what is the pons comprised of?

Back 32

-surface has visible transverse fibers that form a bridge btw the 2 cerebellar hemispheres
-fiber tracts and cranial nerve nuclei make up the rest

Front 33

Where is the medulla oblongata, and what is its major function?

Back 33

-it is the cranial continuation of the spinal cord
-contains important autonomic centers and nuclei for cranial nerves
-medulla controls ANS

Front 34

__= a set of structures containing CSF in the brain; it is continuous with the central canal of the spinal cord

Back 34

ventricular system

Front 35

explain the ventricular system flow..

Back 35

R/L lateral ventricles ( within cerebral hemispheres)
3rd ventricle- connected to the laterla ventricles by 2 interventricular foramina
4th ventricle- connected to the 3rd ventricle via a cerebral aqueduct

Front 36

__= tuft of capillaries that protrudes into the lumen of the ventricles

Back 36

choroid plexxus

Front 37

what are the characteristic features of the spinal cord?

Back 37

-caudal continuation of medulla oblongata
-*gray matter is in the center (butterfly shape) and white matter on the outside
-spinal cord segment has presence of spinal nerves with dorsal/ventral roots

has sensory- ascending tracts
and motor- descending tracts

Front 38

__= connective tissue covering of brain and spinal cord, has3 layers...

___= deepest; delicate membrane that forms a sheath around blood vessels

__= web-like filaments

__= tough fibrous covering of CNS, it fills the role of periosteum in cranium

Back 38

meninges

Pia- mater

arachnoid

duramater

Front 39

What is the significance of the meninges?

Back 39

space btw the pia mater and arachnoid space (imp for spinal taps); found in both cranial and spinal meninges
-epidural space

Front 40

__= system that includes the nerves and ganglia outside the CNS ( spinal/cranial nerves)

-purpose- convey sensory info to brain and spinal cord
-produce mvt of muscles or secretion from glands via motor nerves

Back 40

PNS

Front 41

___= part of the NS that regulates activity in the viscera and structure not under voluntary control
-2 parts= sympathetic/parasympathetic
-2 neurons in series - preganglionic( one from spinal column) , ganglia (junction), postganglionic ( one to organ)

Back 41

ANS

Front 42

___part/system of the ANS located in the thoracolumbar region

__ part/system in the craniosacral region

Back 42

sympathetic

parasympathetic

Front 43

__= a nerves' way of transmitting info; signal sent along a nerve that is very rapid and occurs in axons

Back 43

nerve impulse

Front 44

__= occurs in non-myelinated axons
-wave of repolarization/depolarization simply travels from one part of the membrane to the next adjacent part

Back 44

continuous conduction of nerve impulses

Front 45

__= occurs in myelinated axons
-recall that the myelin sheath is not completed, so there is myelin free regions along the axon, the nodes of ranvier
-impulse leaps

Back 45

saltatory conduction of nerve impulse

"saltare" means, to leap

Front 46

__= occurs at the synapse ( specialized junctions for information exchange btw neurons or neuron and another cell

-excitatory/inhibitory synapses

-synaptic clefts
-neurotransmiters can be removed from the neural synapse via enzymes degrading the NT, cell membrane transport system absorbs NT, NT diffuses away from the area of synapse
-Convergence vs divergence

Back 46

synaptic transmission

Front 47

__= nerve not strictly motor or sensory; has both elements

Back 47

mixed nerve

Front 48

___ system of the ANS prepares for stress(thoracic/lumbar)

__ system of the ANS recovers from stress ( cranial/sacral)

Back 48

sympathetic

parasympathetic

Front 49

___ nerves innervate the region of the body near where they emerge from the vertebral column
-mixed nerves
-dorsal/ventral branches
-plexus- brachial/lumbosacral

Back 49

spinal nerves

Front 50

___ nerves have 12 unpaired nerves numbered by roman numerals
-nerves stemming from the brain
-do not have discernable dorsal/ventral roots
-some are strictly motor or sensory, as opposed to spinal which are all mixed

Back 50

cranial nerves

Front 51

__= NT seen in neuromuscular junctions
-cholinergic neurons ( nicotinic/muscarinic receptors)

__= NT seen in adrenergic neurons/receptors (fight/flight response)

__= most predominant INHIBITORY NT in CNS
-binding to receptor causes hyperpolarization(inhibition)
-used in sedatives, tranquilizers, muscle relaxers

__= predominate EXCITATORY NT in CNS
-receptors in high conc. in brain, memory/learning

Back 51

acetylcholine

norepinephrine

GABA

glutamate

Front 52

__= automatic response to a stimuli

__= entire neural circuit from stimulus detection to response
Ex: spinal reflex= patellar tendon/knee jerk
cranial reflex= corneal relfex

Back 52

reflex


reflex arc

Front 53

___ neuron carries info to the brain

__ neuron causes the effect of the mvt of the muscle

Back 53

sensory

motor

Front 54

explain a reflex arc..

Back 54

patellar tendon stimulated; affarent component goes to the spinal cord with info to the reflex center
-efferent component leaves reflex center and causes mvt

Front 55

discuss the events that occur to start an action potential..

Back 55

stimuli changes permeability to sodium/potassium ions
-alters distribution of charge in cell body, if charge great enough, triggers action potential tomove down axon
-to move down axon, voltage gated channels open/close depending on changes in the membrane
-stimulus cuases sodium voltage gated channels to open, allowing sodium to rush in -cell becomes positive on inside, neg on the outside
-sodium channels quickly close and potassium voltage gated channels open, allowing potassium ions out, pos outside, neg inside again. Potassium channels close.
-sodium ions inside diffuse to adjacent areas causing slight change in polarity, along adjacent part of the membrane
-change in polarity in adjacent areas allows sodium channels to open again, and sodium moves in and action potential travels down the neuron like a wave.
-meanwhile potassium pums open an dpotassium leaves restoring neg in neuron, pos outside
-sodium potassium pump has been shuttling sodium ions outs, potassium ions in by ATP reestablishing resting potential

Front 56

explain how action potential is transferred in the synaptic cleft from a motor neuron to a muscle

Back 56

-as action potential reaches the neuromuscular junction, vesicles containing acetylcholine, fuse with membrane of nerve terminal and ACh is released into the cleft and the molecules diffuse across cleft and bind with ACh receptors and this open sodium potassium ion channels allowing sodium ions to rush into the muscle fiber and potassium ions to diffuse out.
ACh then splits into acetate and choline by cholinesterase resulting in inactivation/closure of the channe.
-flux of ions at openings of channels, brings membrane to threshold, causing voltage gated channesl to open and action potential propagated over entire surface of muscle and into T-tubule system.
-as action potential meets DHP receptors, causes opening of ryanide calcium channel into laterl sac of SR,allowing calcium to diffuse out and into region of myofibrils
-calcium binds to troponin resluting in mvt of troponin/tropomyosin away from myosin binding sites on actin, revealing thebinding sites for the myosin heads on the actin. They bind and the head is bent to 90 degrees and it pulls
-contraction continues as long as action potential continue to reach neuromuscular junction causing concentration of calcium to increase around myofibrils
-to end contraction, calcium must be actively transferred by the calcium pump, calcium ATPase back into lumen of lateral sacs,
-the pump utilizes ATP as sources of energy
- process reduces conc of calcium in area of myofibrils
-calcium then dissociates from troponin and tropomyosin once again covers myosin binding sites on actin and muscle relaxes