new content for lecture exam 3

fuckkk i am scared

ganglion

a swelling or enlargement of a nerve where the soma are

sensory pns

receives information and transmits it to the cns (afferent neurons)

motor pns

sends signals from the cns (efferent neurons)

somatic

skin, muscles, joints, bones

viceral

internal organs

autonomic ns

viceral sensory and motor, organ function regulation

sympathetic

fight or flight

parasympathetic

rest and digest

cerebrum

upper part of brain

cerebellum

mini brain

gyri

folds of brain

sulci

grooves in tissue

longitudinal fissure

separates left and right cerebral hems

frontal lobe

voluntary motor, mood, memory, emotion, planning

parietal lobe

sensory reception, taste

temporal lobe

hearing, smell, learning, memory, emotion

occipital lobe

vision

central sulcus

separates frontal lobe from parietal lobe

lateral sulcus

separates temporal lobe from frontal and parietal lobes above it

Parieto-occipital sulcus

separates parietal lobe from occipital lobe

Precentral  gyrus

anterior to central sulcus – important for initiating motor movements when you move

Postcentral gyrus

posterior to central sulcus, sensory information when its warm or shrap just feeling

gray matter

neuronal dendrites, soma, synapses

white matter

bundles of neuronal axons (Tracts)

cerebral cortex

Outer layer of gray matter of cerebrum (critical thinking)

damage to cerebellum

visual, motor, auditory, time

corpus callosum

linking left and right cerebrum

thalamus

relay center in the brain that receives information and directs it to the different areas of the cerebrum

hypothalamus

major control center 4 autonomic ns and relays messages TO PTG

pituitary gland

master gland- secretes hormones to control other glands

midbrain

connects the cerebrum and cerebellum, pons, and medulla oblongata,

pons

conducts signals between cerebrum and cerebellum. Sends sensory messages to thalamus.

Medulla oblongata

translator of spine and brain also cough and sneeze

Reticular Formation

network of nuclei scattered throughout brainstem. Important for motor control, sleep/consciousness, cardiovascular function, pain perception

meninges

3 layers of CT surrounding brain

dura mater

thickest, outest

falx cerebri

separates right and left hemispheres of cerebrum

tentorium cerebelli

separates cerebellum from cerebrum

arachnoid mater

middle spider layer brain cushion

pia mater

innermost, thinnest layer of meninges

functions of CSF

buoyancy, protection, chemical stability

arachnoid villi

small extensions of the arachnoid mater where CSF is absorbed into bloodstream

pairs of spinal nerves

31

cauda equina

L1 when nerves follow downward

medullary cone

end of spinal cord (L1)

white matter spine

myelinated axons bundled (columns with ascending and descending tracts)

gray matter spine

soma, dendrites, site of synapses

ascending tracts 3

sensory info to brain

descending tracts 2

motor information FROM the brain

decussation

crossover spinal tracts

ipsilateral

same side

contralateral

the tracts decussate

Posterior roots

SENSORY information back to the CNS

Anterior roots

MOTOR information away from the CNS

POSTERIOR RAMUS

local muscles and joints and skin of the back

ANTERIOR RAMUS

ventral and lateral skin and muscles of trunk and limbs

communicating ramus

allows for flow of nerve fibers to/from CNS and sympathetic chain (part of autonomic nervous system)

cervical

C1-C5

BRACHIAL

C1-T1

LUMBAR

L1-L4

SACRAL

L4, L5, S1-S4

sensory afferent neurons

detecting touch, pressure, heat, light info to cns

Interneurons – located exclusively in the CNS

link sensory and motor, process

motor efferent neurons

triggering an action in a muscle, gland, or organ, FROM CNS

schwann cells

surround PNS axons

oligodendrite cells

surround CNS axons

Ependymal cells (CNS)

cuboid-shaped cells (not epithelial) with cilia that line the internal cavities of the brain and spinal cord

microglia (CNS)

phagocytose to protect neuron from infection

astrocytes (CNS)

blood brain barrier

satellite cells (PNS)

nourishment

nodes of ranvier

unmyelinated areas on axon

internodes

are myelinated

Acetylcholine

motor neurons communicate with muscle fibers

diffusion

neurotransmitters diffuse away and get taken by astro

reuptake

taken back up by presynaptic neuron via endocytosis

degration/metabolism

enzymes break neurotransmitters down

temporal summation

one neuron sending signals fast enough to trigger action potential in another

spatial summation

many neurons sending chill signals to trigger another

somatic reflexes

react to physical stimuli

visceral reflexes

altering function of organs (heartbeat fast when low BP)

vagus nerve CN10

preganglionic, digestive, heart, lungs

cholinergic fibers

neurons that release ACh (preganglionic)

adrenergic fibers

neurons that release norepinephrine (postganglionic)