Unit 6: Nervous System / Special Senses Flashcards
what are the functions of the nervous system
sensory, integration, and motor
perceives or senses changes that occur in the body
sensory
interprets the incoming sensory information to formulate a response
integration
the ability to initiate a response such body movement or the secretion from a gland
motor
CNS
central nervous system
what does the CNS consist of
brain and spinal cord
what does the PNS consist of
the nerves which extend from the brain and spinal cord and all else
PNS
peripheral nervous system
how many pair of spinal nerves are there
31 pair
how many pairs of cranial nerves are there
12 pair
ANS
(auto)nomic nervous system; it is automatic like the gun
what are the two divisions of the ANS
sympathetic (SNS) and parasympathetic nervous system (PNS)
nicknamed the fight or flight helps the body to cope with stress or emergency situations. stimulates an increase in heart rate, BG, breathing, etc.
sympathetic nervous system (SNS)
nicknamed “rest and relaxation” helps the body return to homeostasis. the heart rate decreases, blood flow is reduced to skeletal muscles
Parasympathetic nervous system
controls the nerves to the skeletal muscles and the skin as well as the face, eyes, ears, and nose
somatic nervous system
transmit nerve impulses to the brain and spinal cord
afferent nerves
sensory nerves come from the skin, skeletal muscles, or joints, the are called
somatic afferent nerves
sensory nerves come from the body organs, they are called
visceral afferent nerves
transmit nerve impulses from the central nervous system to the organs, muscles, and glands
motor or efferent nerves
are the basic units of the nervous system.
neurons or nerves
detect information from the internal and external environment and transmit the information to the brain and spinal cord
sensory neurons (afferent neurons)
transmit impulses which carry instructions from the brain and spinal cord to tissues, organs, and organ systems
motor neurons (efferent neurons)
are ONLY located in the CNS. they are located between sensory and motor neurons and are responsible for analysis of sensory input and coordinating the motor outputs
interneurons
what are the three basic parts of a neuron
dendrite, cell body, and axon
are short, branching extensions which provide the reception of signals from other neurons. conduct towards the cell body
dendrites
contains a large nucleus, cytoplasm. contains the usual cellular organelles with the exception of centrioles which are necessary for mitosis
cell body
is responsible for carrying nerve impulses to other neurons, muscles or glands
axon
what are the five neuroglial cells
astrocytes microglia oligodendrocytes ependymal cells schwann cells
are the largest and most numerous of all neuroglial cells. located in the CNS. they are star-shaped cells which have numerous projections. located between blood capillaries and neurons.
astrocytes
are spider-like phagocytic cells found in the CNS. they perform phagocytosis to dispose of dead brain cells and infection
microglia
they are found in the CNS. and are responsible for producing the myelin which insulates the axons. helps increase the speed of the action potential
oligodendrocytes
are ciliated cells found in the CNS. ependymal cells line the central canal of the spinal cord and ventricles of the brain. responsible for producing CSF and to circulate it
ependymal cells
are found in the PNS. produce myelin that surrounds the axons. helps insuliate the axons and increases the speed of the action potential along the axon
Schwann cells
regions of the CNS which contain myelinated axons are referred to as
white matter
regions of the CNS which contain mostly nerve cell bodies and unmyelinated axons are referred to as
gray matter
covering around the brain and spinal cord
meninges
the outer layer, “tough mother” is a double layer membrane. attached to the inner surface of the skull
dura mater
the middle layer, “spider mother” has threadlike extensions to span the subarachnoid space, is filled with cerebrospinal fluid
arachnoid
most inner layer, “soft mother” clings tightly to the surface of the brain and spinal cord
pia mater
rapid, predictable, unconscious, and involuntary responses to stimuli
reflex
what are the five components of reflex arcs
(sensory) receptor sensory (afferent) neuron interneuron motor (efferent) neuron effector
detects the incoming stimulus
(sensory) receptor
transmits the action potential to the spinal cord or brain
Sensory (afferent) neuron
in the spinal cord or brain which process the information
interneuron
takes the action potential away from the spinal cord or brain
motor (efferent) neuron
is the response by the muscle, gland, or organ
effector
what are the four principle parts of the brain
Cerebrum
cerebellum
brain stem
diencephalon
is the largest part of the brain and is divided into paired halves. conscious thought process, memory storage and retrieval, sensation, and complex motor patterns originate here
cerebrum
what are the four lobes of the cerebrum (think skull bones)
frontal, parietal, temporal, and occipital
thin outer layer of gray matter on the cerebrum
cerebral cortex
a band that connects the two halves of the cerebrum
corpus callosum***
a series of ridges or bumps on the cerebrum
gyrus (plural gyri)
shallow depressions on the cerebrum
sulcus (plural sulci)
deeper grooves on the cerebrum
fissures
is a large, cauliflower-like structure found inferior to the occipital lobe of the cerebrum; provides the precise timing for coordination of skeletal muscle activity and controls balance and equilibrium. stores memories of previous movement
cerebellum
is a structure of the pons that is responsible for regulating the sleep-wake cycle, attentiveness, and concentration
reticular formation
is superior to the brain stem and is surrounded by the cerebral hemispheres. main structures include the thalamus and hypothalamus.
diencephalon
is a clear, watery fluid similar to blood plasma. it is continuously formed from the blood by the choroid plexus
cerebrospinal fluid
is a cluster of capillaries found in each ventricle of the brain; produces cerebrospinal fluid
choroid plexus
is the most inferior portion of the brain. it is responsible for regulating many vital, unconscious processes. it is composed of three sections
brainstem
what are the three sections of the brainstem
medulla oblongata, pons, midbrain
is the most inferior section of the brain stem extending from the spinal cord. regulates heart rate, blood pressure, breathing, swallowing, coughing, sneezing, and vomiting
medulla oblongata
is a rounded bulge superior to the medulla oblongata. serves as relay station for both sensory and motor nerve impulses as well as regulating the rate and depth of breathing
pons
serves as a relay station for both sensory and motor nerve impulses and contains reflex centers for hearing, vision, and posture
midbrain
composed of gray matter and is divided into two parts
diencephalon
what are the two parts of the diencephalon
thalamus and the hypothalamus
largest section of diencephalon. serves as a relay station for sensory impulses, except for sense of smell.
thalamus
regulates body temperature, water balance and metabolism. it is also important in regulating thirst, hunger, blood pressure, pleasure, and SEX DRIVE :p
hypothalamus
what are the four lobes of the brain
frontal, parietal, temporal, and occipital
lobe that is associated with the control of skeletal muscles, concentration, planning, problem solving, writing, and speech
frontal lobe
is posterior to the frontal lobe. is responsible for the sensations of temperature, touch, pressure, and pain.
parietal lobe
responsible for understanding speech and helping us to use words and express thoughts and feelings
Wernicke’s area (located in the parietal lobe)
forms the posterior portion of each hemisphere. responsible for vision and combining images with other sensory experiences
occipital
communicates with the spinal cord. integrate and analyze information. makes rapid and complex muscular movements possible
cerebellum
delicate wispy, white lines throughout the cerebellum are called the
arbor vitae or tree of life
is the most common motor neuron disease of muscular atrophy. causes of this disease include autoimmune disorders, disturbances in motor neuron enzyme metabolism
Amyotrophic Lateral Sclerosis (ALS) OR Lou Gehrig’s disease
includes progressive changes in the neurons of the brain due to a lack of neurotransmitters in the brain, trauma, and genetics. neurons will degenerate until they can longer carry an impulse.
Alzheimer’s disease
the covering(s) of the brain and spinal cord (usually pia mater) become inflamed, usually the result of bacterial infection. treatment includes early recognition and antibiotic therapy
Bacterial Meningitis
is the most common cause of crippling in children from prenatal or postnatal CNS damage due to fetal anorexia
Cerebral Palsy (CP)
is a condition of the brain marked by susceptibility to recurrent seizures that are associated with abnormal discharges in the neurons of the brain.
epilepsy
is characterized by loss of myelin from the axons of the peripheral nerves. hard, plaque-like structures replace the destroyed myelin and the affected areas are invaded by inflammatory cells. nerve conduction is affected causing weakness, and un-coordination.
multiple sclerosis
is sometimes referred to as the shaking palsy as involuntary tremors are one of the cardinal signs. there is a dopamine (neurotransmitter) deficiency, which prevents brain cells from performing their normal inhibition or stopping nerve impulses within the CNS
Parkinson’s disease
SPECIAL SENSES
FREEBEE
composed of thin skin with eyelashes on the edges
eyelid
is a thin, transparent mebrane lining the eyelids and the outer surface of the cornea
conjuctiva
consists of the lacrimal gland, sac, and nasolacrimal ducts
lacrimal apparatus
produce tears, a dilute salt solution which also contains the enzyme lysozyme.
lacrimal gland
six skeletal muscles located on the outside of the eye
extrinsic muscles
is the thick, outer layer of the eye, divided into two sections
fibrous tunic
what are the two sections of the fibrous tunic
sclera, cornea
forms the majority of the fibrous tunic. composed of fibrous connective tissue and is often called the “white of the eye”
sclera
is nicknamed the “window of the eye” anterior clear portion which bulges slightly outward and allows light to enter the eye
cornea
middle layer of the eye. it contains blood vessels which nourish the eye
vascular tunic
is a thin membrane containing the brown pigment (melanin) to absorb light coming from sides of the eye
choroid
is the thickest part of the vascular tunic. consists of smooth muscle fibers which are attached to the lens by the suspensory ligaments.
ciliary body
is the colored portion of the eye
iris
is the crystalline epithelial structure located behind the iris and the pupil. helps to focus light waves on the retina
lens
the most inner, nervous layer
nervous tunic
is a thin, fragile layer of neurons which form the inner lining of the back of the eye. receives light waves, coverts the information to nerve impulses which are transmitted to the optic nerve
retina
are elongated, cylindrical dendrites which are sensitive to low levels of light. black and white vision
rods
are cells which have dendrites tapered like cones. these cells require bright light and are sensitive to color
cones
is also known as the pinna. is an elastic cartilage structure covered with skin
auricle
is also known as the external auditory canal. this tube extends into the temporal bone.
auditory canal
hair and wax-producing glands which help protect the middle ear
ceruminous glands
is a space which contains the three auditory ossicles
tympanic cavity
the eardrum, is a thin membrane found at the end of the auditory tube and is attached to the three auditory ossicles
tympanic membrane
is a small tube extending from the tympanic cavity into the pharynx. it helps to equalize pressure between the middle ear and atmosphere
auditory (eustachian) tube
are the smallest bones in the body. bones of the ear
auditory ossicles
what are the three auditory ossicles
malleus (hammer), incus (anvil), and the stapes (stirrup)
a series of canals within the temporal bone.
bony labyrinth, labyrinth
a watery-fluid, for the transmission of sound waves
perilymph
is the chamber found between the cochlea and the semicircular canals. helps to maintain its static equilibrium or balancing the body when the body is not in motion
vestibule
are three fluid-filled loops. they help the body maintain dynamic equilibrium
semicircular canals
resembles a small shell as its canals are coiled.
cochlea
the actual organ of hearing
organ of corti
is the normal accommodation power of the eye which occurs as consequence of aging
presbyopia
is the ability to see close objects but not distant ones; nearsightedness
myopia
is the ability to see distant objects but not near ones; farsightedness
hyperopia
is the clouding of the lens resulting from the buildup of proteins and epithelial cells
cataract
commonly called pinkeye, is the inflammation of the conjunctiva
conjunctivitis
is a loss of hearing related to the impairment of the conduction of sound waves through the external and middle ear. wax build-up.
conductive hearing loss
nerve impairment deafness results from damage to the nerves or to the organ of corti
sensorineural deafness
is the build-up of excessive aqueous humor in the anterior cavity of the eye. excess pressure against the retina which reduces the amount of blood reaching the retina
glaucoma
is the progressive degeneration of the central part of the retina or the macula which is necessary for good vision
macular degeneration
infection of the middle ear usually the result of a bacterial infection spread from the mucous membrane of the pharynx through the auditory tube
middle ear infection, otitis media
or cross-eyed occurs when the eye cannot coordinate strabismus is caused by paralysis, weakness or other abnormality affecting the external muscle of the eye
strabismus
is the ringing or clicking in the ears
tinnitus
is dizziness or the sensation of spinning
vertigo
what are the six neuroglial cells
astrocytes microglia oligodendrocytes ependymal cells schwann cells satellite cells
serves as a relay station for both sensory and motor nerve impulses and contains reflex centers for hearing, vision, and posture
midbrain