final exam apk2100c ahlgren UF PART 2

muscles and glands

effectors of nervous system

sensory and motor

PNS breaks down into

somatic and autonomic

motor (efferent) division breaks down into

sympathetic and parasympathetic

autonomic divison breaks down into what

afferent (sensory) neurons

conducting TOWARDS the CNS

efferent (motor) neurons

conducting AWAY from CNS

multipolar neuron

most common type of neuron in CNS

Dendrites

receive sensory info from neighboring neurons

Axons

fibers that extend from the cell body and subdivide into branchlike endings called terminal boutons

----receives info form cell body and transmits it to other cells thru the axon terminals

axon hillock

part of soma, not an axon

-area where membrane potentials are summated before they are transmitted to the axon

initial segment of the axon - trigger zone

very first place of the axon that receives an action potential from axon hillock

-not covered in myelin sheath

synaptic cleft

that actual space where that communication occurs -- its the part that separates the two neurons communicating from one another

myelin sheath

wraps around the length of axon with occasional gaps called nodes of ranvier

-impulses jump BW the nodes

synaptic gap/synapse

space bw neurons/neurons communicate with one another across the synapse thru neurotransmitters

Terminal boutons (axon terminals)

end of the axon where it enlarges and secretes neurotransmitter from the cells

glial cells

cells in the nervous system that support, nourish, and protect neurons

multipolar neuron

A neuron with a single axon and multiple dendrites; the most common type of neuron in the nervous system.

bipolar neurons

A neuron that has only two projections (one axon/one dendrite) from the cell body

unipolar neuron

a neuron with one process extending from its cell body

CNS

interneurons are only found in the

Oligodendrocytes

produce myelin sheaths in CNS

Schwann cells

produce myelin sheaths in PNS

Myelin

multilayered lipoprotein that serves as an electrical insulation for the axon by preventing ions from moving across the plasma membrane

nerve

cluster of axons in PNS

tract

cluster of axons in CNS

Nucleus

cluster of somas in CNS

ganglion

cluster of somas in PNS

white matter

large amounts of myelinated and unmyelinated axons

gray matter

large amounts of cell bodies of interneurons and motor neurons

Epineurium

CT that surrounds the entire nerve

Perineurium

CT surrounding fasicles, which are bundles of axons arranged parallel to one another

Endoneurium

CT found WITHIN the fascicles, surrounding the individual schwann cells that surround individual axons

receptor, sensory neuron, integration center, motor neuron, effector

five components of reflex arc

Rostral

towards the snout

Caudal

towards the tails

Sulci

shallow grooves

Gyri

ridges of the brain

central sulcus

separates frontal and parietal lobes

parieto-occipital sulcus

separates occipital and parietal lobes

lateral sulcus

Separates temporal lobe from parietal and frontal lobes

Fissures

deep grooves in the brain

transverse cerebral fissure

separates cerebrum and cerebellum

longitudinal fissure

separates cerebral hemispheres

dura mater, arachnoid mater, pia mater

list the meninges from superficial to deep

dura mater

thick, outermost layer of the meninges surrounding and protecting the brain and spinal cord

arachnoid mater

weblike middle layer of the three meninges

pia mater

thin, delicate inner membrane of the meninges

---highly vascularized and delicate

---clings to the surface of the brain and spinal cord

third ventricle

The midline ventricle that conducts cerebrospinal fluid from the lateral ventricles to the fourth ventricle.

Fouth ventricle

Immediately in front of cerebellum

anterior horn

supplies frontal lobes and parietal lobes

posterior horn

supplies occipital lobes

inferior horn

supplies temporal lobes

Diencephalon

thalamus, hypothalamus, epithalamus

Thalamus

Relay station for sensory information

Hypothalamus

homeostasis

Midbrain

Region between the hindbrain and the forebrain; it is important for hearing and sight.

Pons

A brain structure that relays information from the cerebellum to the rest of the brain

medulla oblongata

Part of the brainstem that controls vital life-sustaining functions such as heartbeat, breathing, blood pressure, and digestion.

olives of medulla oblongata

rounded; protrude from anterior surface. Nuclei within help regulate balance, coordination, modulation of sound from inner ear

pyramids of medulla

ventrally located columns containing descending motor neurons

cervical, thoracic, lumbar, sacral, coccygeal

regions of the vertebral column from rostral to caudal

externally

in the spinal cord, white matter is located....

internally

in the spinal cord, gray matter is located...

dorsal horn

sensory

ventral horn

motor

root

horns give off small axons that accumulate together to form a...

cell bodies of sensory neurons

The dorsal root ganglia mainly contain

axons of motor neurons

ventral roots contain

cranial nerves

12 pairs of nerves arising from the brain

spinal nerves

31 pairs of nerves arising from the spinal cord

plexus

interlacing network of axons

ventral rami

which rami forms plexuses?

dorsal rami

which rami does NOT form plexuses

C1-C4; phrenic nerve

cervical plexus, innervates diaphragm

C4-T1; brachial plexus

gives rise to ulnar nerve, medial nerve, radial nerve, axillary nerve, and muculocutaneous nerve -- innervated antebrachium and brachium

L1-L4, obturator and femoral nerves

lumbar plexus, helps innervate thigh

L4-S4, sciatic nerve

sacral plexus, supplies lower regions like leg, hamstrings, and buttocks

I Olfactory

SENSORY nerve

-sense of smell

II Optic

SENSORY

-vision

III Oculomotor

motor, eye movement: superior rectus, medial rectus, inferior rectus, inferior oblique muscles

IV Trochlear

motor, eye movement: superior oblique muscle

V Trigeminal

mixed nerve

-chewing and sensation of face

VI Abducens

motor, eye movement: lateral rectus muscle

VII Facial

mixed nerve

facial expression, taste on 2/3 of the tongue, ear sensation, salivary production

VIII Vestibulocochlear

sensory

hearing and balance (equilibrium)

IX Glossopharyngeal

mixed nerve

tongue sensation 1/3 of tongue, swallowing, taste

X Vagus

mixed

swallowing and vocalization, taste in epiglottis, helps the parasympathic nervous system function (heart and digestion)

- only cranial nerve that leaves the head to the ventral cavity

XI Accessory

motor

innervates your upper trapezius fibers and sternocleidomastoid ----- moves your head and neck

XII Hypoglossal

motor

innervates the tongue form under, moves the tongue

Some Say Marry Money But My Brother Says Big Brains Matter More

trick to remembering if a nerve is motor, sensory, or mixed (in order from 1-12)

somatic motor division of PNS

-neurons can only activate skeletal muscle

-impulses are sent form the spinal cord to the skeletal muscle via the neuron of a single axon

visceral (autonomic) nervous system

-neurons can activate or inhibit smooth muscle, cardiac muscle, or glands

-The ANS uses two neurons to send impulses: a preganglionic neuron and postganglionic neuron

lateral horn of spinal cord

-soma of sympathetic preganglionic neuron exists here

-of the thoracocolumbar spinal cord (T1-L2)

T1-L2

preganglionic fibers arise from spinal cord segments :

preganglionic

extends from soma in CNS to ganglion (cell bodies in PNS)

postganglionic

releases acetycholine into synaptic cleft, activating a second neuron in the PNS called postganglionic neuron

---then its sent to the effectors

Norepinephrine

is the neurotransmitter released onto an effector organ in the sympathetic nervous system

Acetylcholine

neurotransmitter released onto an effector organ in parasympathetic nervous system

hypothalmus

regulates autonomic tone

-regulates the balance of sympathetic and parasympathetic activity == autonomic tone

parasympathetic - rest and digest

-salivation

-constriction of pupils

-constriction of bronchi

-slowing of heart beat

-constriction of urinary b ladder

-stimulation of peristalsis

-secretion, bile release