Nervous System Test Flashcards
Function of a neuron
-The basic cell of the nervous system
~Highly specialized cells that transmit messages from one area of the body to another
sensory neuron
- afferent
- convey impulses to the central nervous system from sensory receptors
motor neuron
- efferent
- carry impulses from the CNS to effector organs
association neuron
-Connect sensory and motor neurons
different types of supporting cells
- Astrocytes
- Microglia
- Ependymal Cells
- Oligodendrocytes
- Satellite Cells
CNS
- Central Nervous System
- Brain and Spinal cord
PNS
- Peripheral Nervous System
- Nerves outside brain and spinal cord
autonomic nervous system
-Involuntary
-Only motor nerves
-Divided into two divisions:
~Sympathetic division
~Parasympathetic division
Microglia
Spider-like phagocytes, dispose of debris
sympathetic division
-Sympathetic=”fight-or-flight”
-Response to unusual stimulus
-Takes over to increase activities
Ex: heart rate, breathing, etc…
-Remember as the ‘E’ division (Exercise, Excitement, Emergency, Embarrassment)
-Blood goes from digestive organs to skeletal muscles
-Glucose gets released from liver
-Dilates pupils
-Stimulates perspiration
Satellite Cells
Protect neuron cell bodies
Schwann Cells
Form myelin sheath in the peripheral nervous system
parasympathetic
- Parasympathetic-housekeeping activities
- Conserves energy
- Maintains daily necessary body functions
- Remember as the ‘D’ division (Digestion, Defecation, Diuresis)
- Constricts bronchioles
- Decreases heart rate
- Stimulates saliva
- Digestive secretions increase
- Relaxes sphincter muscles (urinary tract, rectum)
supporting cells
are mitotic and can form tumors
what does myelin do for a nerve impulse
impulses travel faster
reflex arc pathway
Stimulus Afferent neuron Association neuron/Interneuron neuron Efferent Muscle/gland affected
minimum number of neurons in a reflex arc
2 ex: knee jerk
parts of the brain stem
- Midbrain
- Pons
- Medulla Oblongata
medulla oblongata
-Lowest part of brain stem
-Merges with spinal cord
-Functions as an important control center:
~Heart rate, Breathing, Blood pressure regulation, Swallowing, Vomiting
cerebellum
-two hemispheres-convoluted
-Function:
~Involuntary coordination of body movements, times skeletal muscle, controls balance and equilibrium
hypothalamus
-under the thalamus
-Function:
~Autonomic nervous system center
corpus callosum
- Large fiber tract area between cerebral hemispheres
- Allows them to communicate with each other
cerebrum
Paired left and right hemispheres
More than ½ of brain mass
Surface made of ridges (gyri) and grooves (sulci)
broca’s area
- Base of precentral gyrus, on left side of brain only
- Function: allows you to “say” words, damage to this area-you know what you want to say, but you can’t get the words out of your mouth
- Higher intellectual reasoning
pineal gland
Secretes melatonin (aids in sleep)
thalamus
- Surrounds third ventricle
- Function: relay station for sensory impulses
- transfer to correct location for interpretation - impulses cross from left to right side of body or right to left side of body after here
pons
Protrudes just below the midbrain
Function: Controls breathing
optic nerve function
allows you to see
olfactory nerve function
sense nerve of smell
oculomotor nerve function
- stimulates 4 out of 6 eye muscles
- helps pupil to constrict
trigeminal nerve function
sensory fibers for chewing muscle
pons to face-ophthalmic, maxillary, mandible
trochlear nerve function
- motor fibers to superior oblique eye muscle
- moves superior oblique muscle of eye
hypoglossal nerve function
-tongue movement
vagus nerve function
- “wanderer”
- parasympathetic
- motor fibers to heart, lungs, stomach, liver, kidneys, pharynx, larynx, moves food in digestive tract, regulates heart activity
facial nerve function
-chief motor muscle of face (temporal, zygomatic, buccal, mandible, cervical stem: tears/taste buds/salivary glands
vestibucolchear nerve function
hearing, balance
accessory nerve function
- activates sternocleidomastoid and trapez
- moves the muscles to allow you to move head/neck
glossopharyngeal nerve function
stimulate muscles for reflex swallowing (gag reflex, taste buds, posterior tongue)
abducens nerve function
extrinsic eye muscle-move eye laterally
dorsal root
collections of cell bodies outside the central nervous system
ventral root
has axons of motor neurons
spinal nerve
31 pairs
One at each level of vertebrae
Formed from fusion of ventral and dorsal roots
Named for the region in which they arise
pia mater
“gentle mother”
Internal layer
Clings to surface of brain
dura mater
“hard mother”
Double layer external covering
Periosteum-attached to surface of skull
Meningeal layer-outer covering of brain
arachnoid mater
middle layer
Web like
central canal
filled with cerebral spinal fluid
dorsal horn
posterior
ventral horn
anterior
column of white matter
conduction tracts in spinal cord
concussion
- slight brain injury
- Symptoms: Dizzy, “See-stars”, Lose consciousness briefly, Naseau, Vomiting
- No permanents damage
contusion
- marked tissue damage
- Severe contusion-coma
cerebral edema
- swelling of the brain due to inflammatory response to injury, can be bleeding too
- Compresses brain tissue
cervical nerve area of the spinal nerves
- Phrenic nerve
- Serves diaphragm and muscles of shoulder and neck
- When spasm it causes hiccups
lumbar nerve area of the spinal nerves
- Femoral nerve-lower abdomen, buttocks, anterior thighs, skin of upper leg
- Obturator nerve-adductor muscles of medial thigh, small hip muscles, skin of medial thigh and hip joint
sacral nerve area of the spinal nerves
- Sciatic nerve-splits into common fibular and tibial nerves
- Serves lower trunk, posterior surface of thigh, all lower areas of leg, gluteus muscles of hips
- foot drop-inability to dorsiflex foot
- sciatica-inability to extend hip and flex knee
intracranial hemorrhage
may cause medulla oblongata to be wedged into foreman magnum by pressure of blood
Major regions of the neuron
- Cell body
- Processes
Alzheimer’s
- Progressive degenerative brain disease
- Most in elderly
- Causes abnormal protein deposits called plaques and twisted fibers within neurons
- Victims experience memory loss, irritability, confusion, and ultimately, hallucinations and death
multiple sclerosis
- Myelin sheaths get destroyed, converted to hardened sheaths-Sclerosis
- Impulse gets short circuited
- Lose ability to control muscles
- Autoimmune disease
- Protein component is attacked
- No cure, interferon injections
Astrocytes
- Star shaped
- Brace neurons
- Form blood brain barrier between capillaries and neurons
- Control chemical environment of brain
Ependymal Cells
Line cavities of brain and spinal cord
Circulate cerebrospinal fluid
Oligodendrocytes
Produce myelin sheath around nerve fibers in the central nervous system
somatic nervous system
a division of the peripheral nervous system; also called the voluntary nervous system
sympathetic effector organs
smooth muscles and glands
parasympathetic effector organs
-cardiac muscle
parasympathetic body affects
- relaxing after a meal
- blood pressure/heart rate/respiratory rates regulated
- digestive tract actively digesting food
- skin is warm
sympathetic body affects
- pounding heart
- rapid/deep breathing
- sweaty skin
- prickly scalp
- dilated pupils
when does the parasympathetic kick in
eating/relaxing situations
when does the sympathetic kick in
stressful/scared/nervous/etc… situations
pituitary gland
the neuroendocrine gland located beneath the brain that serves a variety of functions including regulation of the gonads, thyroid, adrenal cortex, water balance, and lactation
dorsal root ganglion
a cluster of nerve cell bodies in a posterior root of a spinal nerve
order of nerve areas of the spinal cord
cervical
thoracic
lumbar
sacral
cervical nerve plexus major nerve
phrenic
brachial nerve plexus major nerve
axillary, radial, median, musculocutaneous, ulnar
lumbar nerve plexus major nerve
femoral, obturator
sacral nerve plexus major nerve
none
three pure sensory neurons
olfactory, optic, and vestibulocochlear
cerebral palsy
a neuromuscular disability in which the voluntary muscles are poorly controlled and spastic due to brain damage
senility
forgetfulness, irritability, difficulty in concentrating and thinking clearly, and confusion
meningitis
inflammation of brain and spinal cord membranes, typically caused by an infection
huntington’s disease
An inherited condition in which nerve cells in the brain break down over time
parkinson’s disease
A disorder of the central nervous system that affects movement, often including tremors.
what subdivision does the sympathetic and parasympathetic belong to
the autonomic NS
huntington’s disease prognosis
starts ti show at 40 and is fatal after 15 years
huntington’s disease symptoms
lost body control, seems as if they are in an altered state but they are not, genetic disorder, shaking , confusion, die young
what carries information from the eye
optic nerve
what disease is caused by an autoimmune disease that attacks the protein component of the myelin sheath
multiple sclerosis
fiber tracts go to opposite sides of the cerebrum
Corpus Callosum
a spinal nerve is made up of what
both sensory and motor fibers
myelination in the PNS is the job of
Schwann Cells
involved with sleep and melatonin
pineal gland
what is called by lack of oxygen at birth
Cerebral Palsy
Cerebral Palsy prognosis
stays the same (does not get worse nor better)
impulse conduction os fastest in neurons that are
myelinated
nervous system subdivision the is composed of the cranial and spinal nerves and ganglia
PNS
dentist deadens this nerve with Novocain
trigeminal
regulates body temp, thirst, hunger
hypothalamus
