Chapter 12, 13, 14 Exam Anatomy and Physiology

tract

a bundle of neuronal axons that are all located in a specific area of the cord

anterior gray horns

contain somatic motor neurons

anterior root

contains axons of motor neurons which conduct nerve impulses from the cns to effectors

ependymal cells

form and circulate csf

brain

gray matter on the outside in the

synaptic cleft

the gap between the pre and post-synaptic cells

nissl bodies

the rough er in neurons

subarachnoid space

where csf circulates in the spinal cord

cns

where do most signals that stimulate muscles to contract and glands to secrete originate?

between L1 and L2

where does the spinal cord end (vertebrae)

C3

where is breathing

between 3rd and 4th lumbar vertebrae

where is lumbar puncture done

axon hillock

where the axon joins the cell body

from C4 to T1

where the cervical enlargement is located

from T9-T12

where the lumbar enlargement is located

spinal cord

white matter on the outside in the

less and less white matter as we descend because there are fewer sensory tracts going up and there are fewer motor tracts going down

why does the spinal cord become progressively smaller as it goes down

dendrites

(little trees0 are the receiving end of the neuron; short, highly branched structures that conduct impulses toward the cell body; contain organelles

carpal tunnel syndrome

a common type of median nerve injury that is seen in people who perform repetitive motions of wristlike typing on a computer keyboard

lumbar puncture

a needle is inserted into the subarachnoid space for the purpose of withdrawing csf (for diagnosis or to reduce pressure) or to introduce a drug or contrast agent

Erb's palsy

a paralysis of the arm that most often occurs as an infant's head and neck are pulled toward the side at the same time as the shoulders pass through the birth canal

posterior columns

afferent tracts that convey nerve impulses for discriminative touch, light pressure, vibration, and conscious proprioception

afferent

aka sensory

action potentials

allow communication over long distances within the body

dermatome

an area of skin that is innervated by a single spinal nerve, indicated by the letters and number of a particular segmental nerve

integration

another word for interpretation

filum terminale

arising from the conus medullaris is the ___ an extension of the pia mater that extends inferiorly and anchors the spinal cord to the coccyx

arachnoid mater

attached to the inside of the dura and forms the roof of the subarachnoid space in which cerebral spinal fluid circulates

ganglion

cluster of neuronal cell bodies located in the pns

white matter

composed primarily of myelinated axons

somatic motor neurons

conduct impulses away from the cns towards the skeletal muscles under voluntary control in the periphery

posterior gray horns

consist of somatic and autonomic sensory nuclei

peripheral nervous system

consists of all nervous tissue outside of the brain and spinal cord, and includes nerves, ganglia, enteric plexuses, and sensory receptors

unipolar neurons

contain one process which extends form the body and divides into a central branch that functions as an axon and as a dendritic root; usually used for sensory receptors and stretching information from the extremities

gray matter

contains neuronal cell bodies, dendrites, unmyelinated axons, axon terminals, and neuroglia

posterior root

contains only sensory axons, which conduct nerve impulses from sensory receptors in the skin, muscles, and internal organs into the cns

motor neurons

convey action potentials away from the cns to effectors (muscles and glands) in the periphery through cranial or spinal nerves; most are multipolar

sensory neurons

convey action potentials into the cns through cranial or spinal nerves; most are unipolar

somatic sensory neurons

convey information from sensory receptors in the head, body wall, and limbs towards the cns

cervical enlargement

correlates with the sensory input and motor output to the upper extremities

corticospinal

cortex of the brain to spinal cord; efferent tract

multiple sclerosis

diseases like ____ result from autoimmune destruction of myelin

median nerve injury

either at the plexus or occurring more distally; results in numbness, tingling, pain in palm and fingers

ulnar nerve

funny bone

nodes of Ranvier

gaps in the myelin sheath that appear at intervals along the axon

lumbar enlargement

handles motor output and sensory input to and from the legs

cell body

has a nucleus and cytoplasm; organelles; nissl bodies

bipolar neurons

have one dendrite; one xon; used to convey the special senses of sight, smell, hearing, and balance

multipolar neurons

have several dendrites and only one axon and are located throughout the brain and spinal cord; the vast majority of the neurons in the human body are like this

using ion gradients and a variety of ion channels that open or close in response to specific stimuli

how a cell's rmp is created

8 nerve pairs

how many cervical spinal nerve pairs

1 nerve pair

how many coccygeal nerve pairs

5 nerve pairs

how many lumbar nerve pairs

31

how many pairs of spinal nerves emerge from the cord at regular intervals?

5 nerve pairs

how many sacral nerve pairs

12 nerve pairs

how many thoracic nerve pairs

enteric nervous system

involuntarily controls the gastro-intestinal tract; "brain of the gut"

subdural space

lies between the dura and the arachnoid

electrically excitable

like muscle fibers, neurons are ____. they communicate with one another using two types of electrical signals

phrenic nerve

located at c3

interneurons (association neurons)

mainly located within the cns between sensory and motor neurons; integrate incoming sensory info from sensory neurons and then elicit a motor response by activating the appropriate motor neurons. most are multipolar

axon terminals

many fine processes at the end of the axon. The tips of some of these swell into synaptic end bulbs

transection of the spinal cord

means that ascending and descending tracts are partially or completely severed

vestibulospinal tract

motor tract

Blood brain barrier; form the myelin sheath; make cerebrospinal fluid

neuroglia can:

Dura mater

outermost layer of meminges that encloses the spinal cord

microglia

participate in phagocytosis

neuroglia

play a major role in the support and nutrition of the brain, but they do not manipulate information; maintain the internal environment so that neurons can do their jobs

oligodendrocytes

produce myelin in the cns

schwann cells

produce the myelin sheath around axons in the pns

resting membrane potential

producing electrical signals in neurons depends on the existence of a _______

axon

propagates nerve impulses toward another neuron or effector cell

neurons

receive, process, and transmit information by manipulating the flow of charge across their membranes

cauda equina

roots of the lower spinal nerves that angle down along the filum terminale

epidural space

runs between the dura mater and the more superficial ligamentum flavum (which lines the underside of the bony vertebral lamina

neuroglia

support cells of the nervous system

astrocytes

support neurons in the cns; maintain the chemical environment; form the blood brain barrier

satellite cells

support neurons in the pns

posterior root ganglion

swelling in the posterior root, contains the cell bodies of sensory neurons

synaptic vesicles: neurotransmitter

synaptic end bulbs and other caricosities on the axon terminals of presynaptic neurons contain many tiny membrane-enclosed sacs called _____ that store packet of ______ chemicals

somatic nervous system; autonomic nervous system; enteric nervous system

the PNS is divided into:

brain and spinal cord

the central nervous system consists of the ___

conus medullaris

the end of the spinal cord

spinal nerves

the paths of communication between the pinal cord and specific regions of the body; arranged in fascicles surrounded by a perineurium with the entire nerve sheathed by a ct epineurium

denticulate ligaments

the pia mater has 21 pairs of these which attach it to the arachnoid and dura mater; provide stability for the spinal cord

myelination

the process of forming a myelin sheath which electrically insulates the axon of a neuron and increases the speed of nerve impulse conduction

synapse

the site of communication between two neurons or between a neuron and another effector cell

synaptic end bulbs

the swellings at the tips at some axon terminals; bulb shaped

sense, interpretation, response

three fundamental steps of the nervous system

spinothalamic tract

tract that travels from spinal cord to brain; afferent; transmits general somatic sensations

results in death by asphyxiation

transection at the base of the skull

results in paraplegia

transection between cord enlargements

results in quadriplegia

transection in the upper cervical area

pia mater

transparent; pressed up agains the cord and is filled with blood vessels that supply nutrients to it

parasympathetic and sympathetic

two branches of autonomic nervous system

central nervous system and peripheral nervous system

two branches of nervous system

roots

two bundles of axons that connect each spinal nerve to a segment of the cord

astrocytes; oligodendrocytes; microglia; ependymal cells

types of neuroglia in the cns

schwann cells; satellite cells

types of neuroglia in the pns

graded potentials

used for short distance communication