A&p Final 2

Front 1

Structure of spinal cord Ends between:

Back 1

Ends between vertebrae L1 and L2

Front 2

Enlargements of the Spinal Cord
Caused by:

Back 2

Amount of gray matter in segment
Involvement with sensory and motor nerves of limbs

Front 3

Cervical enlargement

Back 3

Nerves of shoulders and upper limbs

Front 4

The Distal End
Conus medullaris:
Filum terminale:
Cauda equina:

Back 4

-thin, conical spinal cord below lumbar enlargement
-thin thread of fibrous tissue at end of conus medullaris
attaches to coccygeal ligament
-nerve roots extending below conus medullaris

Front 5

how many spinal cord segments
Cervical nerves are named for:
All other nerves are named for:

Back 5

31 Spinal Cord Segments
are named for inferior vertebra
are named for superior vertebra

Front 6

Roots
Two branches of spinal nerves
Ventral root contains:
Dorsal root contains:
Dorsal root ganglia contains:

Back 6

-contains axons of motor neurons
-contains axons of sensory neurons
-contain cell bodies of sensory neurons

Front 7

Dorsal and ventral roots join To form a:

Back 7

spinal nerve

Front 8

Mixed Nerves Carry both:

Back 8

Carry both afferent (sensory) and efferent (motor) fibers

Front 9

The Dura Mater (Tough and fibrous)
Cranially: -Fuses with
-Is continuous with

Caudally: -Tapers to
-Joins

Back 9

-Fuses with periosteum of occipital bone
-Is continuous with cranial dura mater

-Tapers to dense cord of collagen fibers
-Joins filum terminale in coccygeal ligament

Front 10

The Epidural Space
Between:
site for:
Contains:
Subarachnoid space is between:

Back 10

-Between spinal dura mater and walls of vertebral canal
-Anesthetic injection site
-Contains loose connective and adipose tissue
-Between arachnoid mater and pia mater

Front 11

Gray matter
Surrounds:
Contains:
Has projections:

Back 11

-Surrounds central canal of spinal cord
-unmyelinated axons
-Has projections (gray horns)

Front 12

White matter
-Contains:

Back 12

Contains myelinated and unmyelinated axons

Front 13

Connective tissue layers of spinal nerves:
Epineurium:
-Dense network of :
Perineurium:
-Divides nerve into:
Endoneurium:
-Surrounds:

Back 13

Outer layer
-Dense network of collagen fibers
Middle layer
-Divides nerve into fascicles (axon bundles)
Inner layer
-Surrounds individual axons

Front 14

Nerve plexuses- (definition,four major plexuses) EACH INCLUDES AND INNERVATES ?
The Cervical Plexus of the Ventral Rami :
The Brachial Plexus of the Ventral Rami
The Lumbar Plexus of the Ventral Rami
The Sacral Plexus of the Ventral Rami

Back 14

Complex, interwoven networks of nerve fibers
The Cervical Plexus of the Ventral Rami
-Includes ventral rami of spinal nerves C1–C5
-Innervates neck, thoracic cavity, diaphragmatic muscles
The Brachial Plexus of the Ventral Rami
• Includes ventral rami of spinal nerves C5–T1
• Innervates pectoral girdle and upper limbs
The Lumbar Plexus of the Ventral Rami
• Includes ventral rami of spinal nerves T12–L4
• innervate the pelvic girdle and lower limbs
The Sacral Plexus of the Ventral Rami
• Includes ventral rami of spinal nerves L4–S4
• innervate the pelvic girdle and lower limbs

Front 15

Motor nerve
white ramus: carries what to what:

Back 15

carries visceral motor fibers to sympathetic ganglion of autonomic nervous system

Front 16

gray ramus:
-return from:
-rejoin:

Back 16

unmyelinated nerves
-return from sympathetic ganglion
-rejoin spinal nerve

Front 17

Dorsal and ventral rami
dorsal ramus:
contains ____ and ____
innervates :

Back 17

-contains somatic and visceral motor fibers
-innervates the back

Front 18

ventral ramus:
• larger branch
• innervates :

Back 18

ventral ramus:
• larger branch
• innervates ventrolateral structures and limbs,

Front 19

dorsal, ventral, and white rami also carry _____ information in addition to motor impulses

Back 19

dorsal, ventral, and white rami also carry sensory information n addition to motor impulses

Front 20

Sensory neurons
-Deliver information to
Motor neurons
-Deliver commands to
Interneurons:

Back 20

Sensory neurons
-Deliver information to CNS
Motor neurons
-Deliver commands to peripheral effectors
Interneurons
-Interpret, plan, and coordinate signals in and out

Front 21

Neuronal Pools
Functional groups of:
Each with limited input sources and output destinations
May stimulate or depress parts of :

Back 21

Neuronal Pools
-Functional groups of interconnected neurons (with the help of interneurons)
Each with limited input sources and output destinations
May stimulate or depress parts of brain or spinal cord

Front 22

Divergence:
Convergence:
Serial processing:
Parallel processing:
Reverberation:

Back 22

-Divergence
Spreads stimulation to many neurons or neuronal pools in CNS
-Convergence
Brings input from many sources to single neuron
-Serial processing
Moves information in single line
-Parallel processing
Moves same information along several paths simultaneously
-Reverberation
Positive feedback mechanism
Functions until inhibited

Front 23

Reflexes- five steps in neural reflex:

Back 23

Step 1: Arrival of stimulus, activation of receptor
Physical or chemical changes
Step 2: Activation of sensory neuron
Graded depolarization
Step 3: Information processing by postsynaptic cell
Triggered by neurotransmitters
Step 4: Activation of motor neuron
Action potential
Step 5: Response of peripheral effector
• Triggered by neurotransmitters,
Four classifications of reflexes and examples:

Front 24

Four classifications of reflexes and examples:

Back 24

- Development
-Motor Response
-Complexity of Neural Circuit
-Site of Information Processing

Front 25

Development
How reflex was developed
innate:
acquired:

Back 25

Innate reflexes:
• basic neural reflexes
• formed before birth e.g sucking, grasping, withdrawal, blinking
Acquired reflexes:
• rapid, automatic
• learned motor patterns e.g shielding a blow, covering ear from noise

Front 26

Motor Response
Nature of resulting motor response
• Somatic reflexes:
• Visceral reflexes (autonomic reflexes):

Back 26

-Somatic reflexes:
• involuntary control of muscular system
• superficial reflexes of skin, mucous membranes
• stretch or deep tendon reflexes (e.g., patellar, or “knee-jerk”, reflex)
-Visceral reflexes (autonomic reflexes):
• voluntary control of systems other than muscular.g contraction of the muscles of the intestine during peristalsis(digestion)

Front 27

Complexity of Neural Circuit
• Monosynaptic reflex
• Polysynaptic reflex

Back 27

-Sensory neuron synapses directly onto motor neuron
stretch reflex, which provides automatic regulation of skeletal muscle length.
-At least one interneuron between sensory neuron and motor neuron
The tendon reflex monitors the external tension produced during a muscular contraction and prevents tearing or breaking of the tendons. Also withdrawal reflexes move affected parts of the body away from a stimulus..

Front 28

Site of Information Processing
• Spinal reflexes

• Cranial reflexes

Back 28

Site of Information Processing
• Spinal reflexes
• Occurs in spinal cord
• Cranial reflexes
• Occurs in brain,monosynaptic, polysynaptic, postural, tendon, withdrawal.

Front 29

Reflex arcs.
Crossed Extensor Reflexes:

Back 29

Crossed Extensor Reflexes
-For example, flexor reflex causes leg to pull up
Crossed extensor reflex straightens other leg
To receive body weight
Maintained by reverberating circuits

Front 30

Characteristics of polysynaptic reflexes

Back 30

Involve pools of neurons
Are intersegmental in distribution
Involve reciprocal inhibition
Have reverberating circuits
Which prolong reflexive motor response
Several reflexes cooperate to produce coordinated, controlled response

Front 31

Babinski:

Back 31

The plantar reflex (negative Babinski reflex), a curling of the toes, is seen in healthy adults.
-The banbiski sign(positive feedback) occurs in the absence of descending inhibition. It is normal in infants, but pathological in adults.

Front 32

Brain alteration of spinal reflexes:
Integration and Control of Spinal Reflexes
-Reflex behaviors are automatic but

-Automatic reflexes can be activated by brain as needed by using few nerve impulses to control
Walking, running, jumping

Back 32

Brain alteration of spinal reflexes: Integration and Control of Spinal Reflexes
-Reflex behaviors are automatic but processing centers in brain can facilitate or inhibit reflex motor patterns based in spinal cord
-Automatic reflexes can be activated by brain as needed by using few nerve impulses to control complex motor functions like Walking, running, jumping.

Front 33

Voluntary Movements and Reflex Motor Patterns
Higher centers of brain incorporate:

Back 33

-Voluntary Movements and Reflex Motor Patterns
Higher centers of brain incorporate lower, reflexive motor patterns

Front 34

Reinforcement of Spinal Reflexes:
Higher centers reinforce spinal reflexes by:
Creating ____ at reflex motor neurons and facilitating _____ neurons

Back 34

Reinforcement of Spinal Reflexes:
Higher centers reinforce spinal reflexes by stimulating excitatory neurons in brain stem or spinal cord, creating EPSPs at reflex motor neurons and facilitating postsynaptic neurons

Front 35

Inhibition of Spinal Reflexes:
Higher centers inhibit spinal reflexes by
Stimulating ______ neurons
Creating _____ at reflex motor neurons and ______ postsynaptic neurons

Back 35

Inhibition of Spinal Reflexes:
Higher centers inhibit spinal reflexes by
Stimulating inhibitory neurons
Creating IPSPs at reflex motor neurons
Suppressing postsynaptic neurons

Front 36

Neurotransmitters:

Back 36

Norepinephrine (NE)
• Dopamine
• Serotonin
• Gamma aminobutyric acid (GABA)

Front 37

Classes of opioids:

Back 37

(relieve pain by reducing the intensity of pain signals to the brain)
Enkephalins
Endomorphins
Dynorphins

Front 38

The larger the diameter,

Back 38

The larger the diameter, the lower the resistance(the faster it'll go down the axon)

Front 39

Excitatory postsynaptic potential (EPSP):
Inhibitory postsynaptic potential (IPSP):
Presynaptic inhibition:
Presynaptic facilitation:

Back 39

-Graded depolarization of postsynaptic membrane
-Graded hyperpolarization of postsynaptic membrane
-Action of an axoaxonic synapse at a synaptic knob that decreases the neurotransmitter released by presynaptic membrane
-Action of an axoaxonic synapse at a synaptic knob that increases the neurotransmitter released by presynaptic membrane.

Front 40

Two methods of propagating action potentials
Continuous propagation:
Saltatory propagation:

Back 40

Continuous propagation: unmyelinated axons(slower process because it's unmyelinated so it can affect one axon at a time)
Saltatory propagation: myelinated axons.(faster and uses less energy),Moves action potentials generated in axon hillock
Along entire length of axon
A series of repeated actions, not passive flow

Front 41

Ion Movements and Electrical Signals.
Five main membrane processes in neural activities
resting potential:
graded potential:
action potential:
synaptic activity:
information processing:

Back 41

resting potential: The transmembrane potential of resting cell, graded potential: Temporary, localized change in resting potential.Caused by stimulus, action potential: Is an electrical impulse.Produced by graded potential. moves along axon, synaptic activity: Releases neurotransmitters at presynaptic membrane. Produces graded potentials in postsynaptic membrane, information processing: Response (integration of stimuli) of postsynaptic cell.

Front 42

Four types of neuroglia in CNS-
ependymal cells:
astrocytes:
oligodendrocytes:
microglia:

Back 42

Four types of neuroglia in CNS-
ependymal cells: Line central canal of spinal cord and ventricles of brain,
astrocytes: Maintain blood–brain barrier (isolates CNS),
oligodendrocytes: Wrap around axons to form myelin sheaths in CNS,
microglia: immune defense in CNS.

Front 43

Types of sensory receptors- interoceptors:
exteroceptors:
proprioceptors:

Back 43

Types of sensory receptors-
interoceptors: Monitor internal systems (digestive, respiratory, cardiovascular, urinary, reproductive) -Internal senses (taste, deep pressure ,pain.) exteroceptors: External senses (touch, temperature, pressure)-Distance senses (sight, smell, hearing), proprioceptors: Monitor position and movement (skeletal muscles and joints).

Front 44

Functional classifications of neurons-
sensory:
motor:
interneurons:

Back 44

Functional classifications of neurons-
sensory: Afferent neurons of PNS,
motor: Efferent neurons of PNS,
interneurons: Association neurons serves as link btwn sensory & motor neurons.

Front 45

Structural classifications of neurons-
anaxonic: Found in
bipolar: Found in
unipolar: Found in
multipolar: Common in the ____,Include all ___

Back 45

Structural classifications of neurons-
anaxonic: Found in brain and sense organs,
bipolar: Found in special sensory organs (sight, smell, hearing),
unipolar: Found in sensory neurons of PNS, multipolar: Common in the CNS,Include all skeletal muscle motor neurons.