SBC neuroscience quiz

what myelinates in the PNS

schwann cells

what myelinates in the CNS

oligodendrocytes

what does myelination allow for

insulation of axons

fast electrical signals

what is the order of the impulse transmission process

signal reception

signal integration

signal conduction

signal transmission

what is meant by signal reception

incoming signals received and converted in change in membrane potential

what is meant by signal integration

change in membrane potential initiates action potential

what is meant by signal conduction

action potential are conducted to the axon terminals

what is meant by signal transmission

neurotransmitter release transmits a signal to the target area

where does anterograde transprt move to

axon terminal

what does retrograde transport move towards

cell body

what are the three meningeal layers

dura mater

arachnoid mater

pia mater

what are the layers of the dura mater

dura mater (endosteal layer)

dural sinus

dura mater (meningeal layer)

what are the layers of the arachnoid mater

arachnoid membrane

subarachnoid space

arachnoid trabeculae

what is the pia mater bound to

surface of the brain by astrocytes

what is the role of the dura mater

protect brain and spinal cord

mechanical strength

covers each nerve root with DRG

drain the brain

what are the characteristics of the dura mater (not what does it do)

thickest layer

pain sensitive

own blood supply surrounds brain and spinal cord

what are some characteristics of the arachnoid mater

more delicate

web like projection

avascular

barrier function

what are the characteristics of the pia mater

cover CNS with neural tissue

thin layer

highly vascularized

what do the dentate ligaments connect

pia mater to dura mater

what are the dentate ligaments

pia projections

band of fibrous pia mater extending along the spinal cord on each side between dorsal and ventral roots

where do the dentate ligaments have a strong attachment

upper cervical

what is the role of the dentate ligaments

support/stability of the spinal cord

what does the brain do

perception and processing of sensory stimuli

execution of voluntary motor response

regulate homeostatic mechanisms

what are the PNS nerves

fibers of sensory and motor neurons (somatic and autonomic)

what is the digestive tract

enteric nervous system

responsible for autonomic function

can operate without brain and spinal cord

what does the spinal cord do

initiate reflexes from gray matter, ventral, and lateral horn

pathway for sensory function between periphery and brain

what do the ganglia do

reception of sensory stimuli by dorsal root and cranial ganglia

relay of visceral motor responses by autonomic ganglia

what are some examples of sympathetic function

dilation of pupils and bronchioles of the lungs

increase HR, blood glucose, blood to skeletal muscles

slow peristatic action

decrease glandular secretion, blood to digestive organs

relax muscles of the gallbladder and urinary bladder

what are examples of structures that contain sympathetic nerves

thoracic and lumbar regions of the spinal cord join prevertebral ganglion and connect to vital organs

what are some examples of parasympathetic nerve function

constrict pupils and bronchioles of the lungs

decrease HR, blood glucose, blood to skeletal muscles

increase peristaltic action, glandular secretion, blood to digestive organs

contract muscles of gallbladder and urinary bladder

what are some examples of structures in the parasympathetic system

brainstem and sacral region of spinal cord to join nerve fibers in muscles and glands

where is the preganglionic neuron in a parasympathetic system

usually in the brain stem or sacral spinal cord

where is the preganglionic neuron in a sympathetic system

usually in the spine

what neurotrasnmitter is released from a parasympathetic preganglionic synapse

acetylcholine

where are parasympathetic postganglionic neurons typically

in a ganglion near target organ

where are sympathetic postganglionic neurons typically

soma in sympathetic ganglion next to the spinal cord

what neurotransmitters are released from parasympathetic postganglionic synapses

acetylcholine or nitric oxide

what neurotransmitters are released from postganglionic synapse

norepinephrine

what is the overall response from the parasympathetic system

rest and digest

what is the overall response from the sympathetic system

fight or flight

what does the cerebral cortex do

ultimate control and information processing center

what does the hypothalamus do

control maintenance functions such as eating

help govern endocrine system

linked to emotion and reward

what does reticular formation do

help control arousal

what does the medulla do specifically

control heartbeat and breathing

what is the amygdala linked to

emotion

what is the hippocampus linked to

memory

is the olfactory bulb part of the limbic system

no

entire rhinencephalon overlaps the limbic system

what is the corticolimbic system important for

learning

plasticity

how pain is perceived

how does the corticolimbic system influence learning, plasticity, and how pain is perceived

focusing attention, motivation and emotions to related particular activities or events

why is the hypothalamus so important

master integrator/coordinator of neuroendocrine activity by monitoring sensory inputs from multiple sources in CNS and PNS to direct appropriate homeostatic responses

what do nerve ending secrete

neurohormones

what do neurohormones from the hypothalamus stimulate or inhibit

release of anterior pituitary hormones

what does the submucosa plexus contain

sensory cells that communicate with the myenteric plexus and motor fibers that stimulate secretion of fluids into the lumen

what does the myenteric plexus contain

neurons responsible for regulating the enzyme output of adjacent organs

do nerve enter the lumen

no nerves where digestion occured

what organs monitor the condition of the lumen

brains in head and gut

what does the mesentery attach to

bowel to the body wall and contains major arteries veins lymphatics and external valves

what does the brain influence in the gut

motility

secretion

nutrient delivery

microbial balance

what can the gut influence

neurotransmitters

stress/anxiety

mood

behavior

what is reticular formation

web of brainstem nuclei and neurons

important relay center between higher centers and the spinal cord regulation of consciousness, posture, emotion processing and visual coordination

how do pain signals reach the cortex

via reticular formation

what are examples of CNS reflex centers

cortex

thalamus

hypothalamus

meninges

what are some examples of vestibular system reflex centers

H1 receptor?

M1 receptor

what are some examples of chemoreceptor trigger zone reflex centers

chemoreceptors

D2 receptor

NK1 receptor?

5-HT3 receptor

what are the reflex centers for vomiting center

H1 receptos

M1 receptor

NK1 receptor

5-HT3 receptor

what are exapmles of GI tract and heart reflex centers

mechanoreceptors

chemoreceptors

5-HT3 receptor

what are examples of autonomic reflex centers in the brainstem

CNS

vestibular system

chemoreceptor trigger zone

vomiting center

GI tract and heart

what kind of information flows into the dorsal horn

afferent sensory information

what kind of information flows into the ventral horn

efferent signals to muscles and gl

what are examples of motor (efferent) and descending pathways (red)

pyramidal tracts

extrapyramidal tract

what are examples of sensory and ascending (afferent) pathways

dorsal column medial lemniscus system

spinocerebellar tracts

anterolateral system

what does the anterior spinothalamic tract do

crude touch/pressure

what does the lateral spinothalamic tract do

pain

temperature

what does the spinocerebellar tract to

proprioception

what does the spinoreticular tract do

deep

chronic pain

what do the posterior/dorsal columns (medial lemniscus) do

proprioception

vibration

tactile stimulation

what can go wrong in the posterior/dorsal column

fasciculus cuneatus

fasciculus gracilis

where do the dorsal columns/medial lemniscal go to

medulla then cross to form medial lemniscus across thalamus then to cortex

where does teh spinothalamic tract go to

ascend one or two ipsilateral spinal cord segments then cross to frontralateral segment of the spinal cord then ascend to thalamus

where do the spinocerebellar tract go to

ventral tracts ascend to contralateral and ipsilateral cerebellum

what does the spinoreticular tract do

convey deep and chronic pain

what kind of pathway is a neospinothalamic

fast pain pathway

what kind of fibers does teh neospinothalamic tract use

A-delta fibers

what kind of tract is the paleospinothalamic tract

slow chronic poorly localized pain

what kind of fibers does the paleospinothalamic tract use

C-fibers

what characteristics are nerves classified by

diameter

degree of myelination

speed of conduction

what are the cutaneous fibers

A-alpha

A-beta

A-delta

C-fibers

what are the afferent fibers from visceral interoceptors

A-delta

C-fibers

what are the characteristics of A-alpha fibers

fastest/largest

heavily myelinated

proprioception

somatic efferent as well

what are the characteristics of A-beta fibers

touch

large

fast pain

myelinated

what sensations are A-beta fibers responsible for

touch/fine touch

vibration

2 pt discrimination

proprioception (spindle sensing length)

what do A-delta fibers sense

sharp initial pain

pain and temp

are A-delta fibers myelinated?

yes

are A-delta fibers afferent or efferent

afferent

what do C-fibers sense

slow nociception

touch

temp

dull aching pain

are C-fibers myelinated or unmyelinated

unmyelinated ar

are C-fibers efferent or afferent

efferent

what are the somatic motor neurons

A-alpha

A-gamma

what are examples of autonomic fibers

B

C-fibers

describe B-fibers

preganglionic autonomic efferent

thin myelination