Structures of the nervous system

tigrebright's version from 2015-10-24 18:01

Section 1

Question Answer
central nervous systemthe brain & spinal cord
peripheral nervous systemincludes the cranial nerves extending from the brain and spinal nerves extending outward from the spinal cord
nerveone or more BUNDLES OF NEURONS that connect the brain and the spinal cord with other parts of the body
tracta BUNDLE OF NERVES located within the brain or spinal cord
gangliona NERVE CENTER made up of a CLUSTER OF NERVE CELL BODIES outside the central nervous system
innervationthe SUPPLY OF NERVES to a specific body part
plexusa NETWORK of intersecting spinal nerves
receptorssites in the sensory organs that RECEIVE external stimulation and send the stimulus through the sensory neurons to the brain for interpretation
stimulusanything that EXCITES a nerve and causes an inpulse
impulsea WAVE OF EXCITATION transmitted through nerve fibers and neurons
reflexan automatic, involuntary response to some change; either inside or outside the body
neuronsthe BASIC CELLS of the nervous system that allow different parts of the body to communicate with each other
brain wavespatterns of neuron electrical activity

Section 2

Question Answer
dendritesthe root-like processes that receive impulses and conduct them to the cell body
processa structure that extends out from the cell body
axona process that conducts impulses away from the nerve cell
terminal end fibersbranching fibers at the end of the axon that lead the nervous impulse from the axon to the synapse
synapsethe space between two neurons or between a neuron and a receptor organ
neurotransmitterschemical substances that make it possible for messages to cross from the synapse of a neuron to the target receptor
acetylcholinereleased at some synapses in the spinal cord and at neuromuscular junctions; it influences MUSCLE ACTION
dopaminereleased within the brain; it is believed to be involved in MOOD AND THOUGHT disorders and in abnormal movement disorders such as Parkinson's
endorphinsnaturally occurring substances that are produced by the brain to help RELIEVE PAIN
norepinephrineaffects ALERTNESS AND AROUSAL, increasing blood pressure and heart rate, and releasing stores of glucose in response to stress. it is also a hormone release by the adrenal gland as part of the body's FIGHT OR FLIGHTresponse
seratoninis released by the brain, and has roles in HUNGER, SLEEP AND PLEASURE RECOGNITION; also sometimes linked to mood disorders
glial cellsprovide SUPPORT AND PROTECTION FOR NEURONS. their 4 main functions are 1. to surround neurons and hold them in place 2. to supply nutrients and oxygen to neurons 3. to insulate one neuron from another 4. to destroy and remove dead neurons

Section 3

Question Answer
myelin sheaththe protective covering made up of glial cells. it forms the white matter of the brain and covers some parts of the spinal cord and the axon of most peripheral nerves
white matterthe portion of the nerve fibers that are myelinated
myelinatedhaving a myelin sheath
gray matterthe portion of the nerve fibers that are unmyelinated.
unmyelinatedlacking a myelin sheath
meningesthe system of membranes that enclose the brain and spinal cord
dura materthe thick, tough, outermost membrane of the meninges
epidural spacethe inner surface of the vertebral column; it contains fat and supportive connective tissues to cushion the dura mater
subdural spacelocated between the dura mater and the arachnoid membrane
arachnoid membranethe second layer of the meninges located between the dura mater and the pia mater; it is loosely attached to the other meninges to allow space for fluid to flow between the layers
subarachnoid spacelocated below the arachnoid membrane and above the pia mater and contains cerebrospinal fluid

Section 4

Question Answer
pia materthe third layer of the meninges, located NEAREST to the brain and spinal cord; it consists of DELICATE CONNECTIVE TISSUE that contains a rich supply of BLOOD VESSELS
cerebrospinal fluidproduced by special capillaries within the four ventricles located in the middle region of the cerebrum; it is a CLEAR, COLORLESS, WATERY fluid that flows throughout the BRAIN and around the SPINAL CORD
functions of cerebrospinal fluidto COOL AND CUSHION the brain and spinal cord from shock and injury;NOURISH the brain and spinal cord by transporting nutrients and chemical messengers to these tissues
cerebrumthe largest and uppermost portion of the brain; responsible for all THOUGHT, JUDGEMENT, MEMORY and EMOTION as well as for controlling and integrating MOTOR AND SENSORY FUNCTIONS
cerebralpertaining the the cerebrum or to the brain
cerebral cortexthe outer layer of the cerebrum and is made up of elevated folds and deep fissures
gyrithe ELEVATED FOLDS of gray matter in the cerebral cortex
sulcithe FISSURES of the cerebral cortex
corpus callosumconnects the left and right cerebral hemispheres
left cerebral hemispherecontrols the majority of the functions on the right side of the body
right cerebral hemispherecontrols the majority of the functions of the left side of the body

Section 5

Question Answer
cerebral lobessubdivision of the cerebral hemispheres; each lobe is named for the bone of the cranium that covers it
frontal lobecontrols skilled motor functions, memory and behavior
parietal lobereceives and interprets nerve impulses from SENSORY RECEPTORS in the TONGUE, SKIN AND MUSCLES
occipital lobecontrols eyesight
temporal lobecontrols the senses of hearing and smell, and the ability to create, store, and access new information
thalamusproduces SENSATIONS by relaying IMPULSES TO AND FROM the cerebrum and the sense organs of the body
hypothalamuscontrols 7 major REGULATORY FUNCTIONS of the brain
cerebellumreceives incoming messages regarding movement within joints, muscle tone, and positions of the body; then relayed to the different parts of the brain that control the MOTIONS OF THE SKELETAL MUSCLE
functions of the cerebellumto produce SMOOTH and COORDINATED MOVEMENT, to maintain EQUILIBRIUM and to sustain normal postures

Section 6

Question Answer
brainstemthe stalk-like portion of the brain that connects the cerebral hemispheres with the spinal cord
mid brain and ponzprovide CONDUCTION PATHWAYS to and from the higher and lower centers in the brain;also control REFLEXES for movements of the EYES AND HEAD in response to visual and auditory stimuli
medulla oblongatait controls BASIC SURVIVAL FUNCTIONS, including the muscles that make possible respiration, heart rate and blood pressure, as well as reflexes for coughing, sneezing, and vomiting
the spinal cordcontains all the nerves that affect the limbs and lower part of the body, and serves as the pathway for impulses traveling to and from the brain;
functions of the hypothalamus1.REGULATES and integrates the AUTONOMIC NERVOUS SYSTEM, including controlling heart rate, blood pressure, respiratory rate, and digestive tract activity; 2. regulates EMOTIONAL RESPONSES, including fear and pleasure; 3. regulates BODY TEMPERATURE; 4. controls HUNGER sensations; 5. controlsTHIRST sensations; 6. regulates SLEEP/WAKE cycles; 7. regulates the PITUITARY GLAND and ENDOCRINE SYSTEM activity
autonomic nerve fiberscarry instructions to the organs and glands from the autonomic nervous system
sensory nerve fibersreceive external stimuli and transmit this information to the brain where it is interpreted
somatic nerve fibers AKA motor nerve fibersconvey information that controls the body's VOLUNTARY MUSCULAR MOVEMENTS
cranial nervesoriginate from the under surface of the brain
peripheral spinal nervesgrouped together and named based on the region of the body they innervate
autonomic nervous systemcontrols the INVOLUNTARY ACTIONS of the body such as the functioning of internal organs; two parts- sympathetic nerves and parasympathetic nerves
sympathetic nervesprepare the body for emergencies and stress by increasing the breathing rate, heart rate, and blood flow to muscles
fight or flight responsethe body's natural reaction to real or imaginary danger
parasympathetic nervesreturn the body to normal after response to stress; also maintain normal body functions during ordinary circumstances