Ametropia

The Central Nervous System contains

Brain and Spinal Cord

Sensory

senses stimulus from both body and external environment

Integrative

analyzes interprets and stores information about stimulus it receives

Motor

respods to stimuli, muscular contraction and glandular secretion

Peripheral Nervous System

contains spinal nerves, cranial nerves and subdivisions are Somatic and Autonomic

CNS jobs

sorts incoming sensory information, generates thoughts and emotions, forms and stores memories, stimulates muscle contractins, stimulates glandular secretions

PNS jobs

connect sensory receptors, muscles and glands to CNS, and Afferent & Efferent neurons

Somatic Nervous System(PNS)

convey info from skin/special senses to CNS & contain motor neurons from CNS that conduct impulses to skeletal muscles.

Autonomic Nervous System

From viscera(internal organs) to CNS, contain efferent neuronsthat conduct impulses to smooth and cardia muscle nad glands

Sympathetic

Stimulatory effect (fight or flight)

Parasympathetic

Inhibitory effect (rest and digest)

Neuron jobs

sensing, remembering, thinking, control muscle activity, control glandular secretion

Synapse

relay point betwee 2 neurons or neuron & effector

Cell Body contains

nucleus, cytoplasm, organelles

Dendrites

Afferent, branched processes

Axon

long thin cylindrical process, Efferent function

Astrocytes (CNS or PNS?) -

CNS, forms blood-brain barrier, link between brain and blood vessels, star shaped

Oligodendrocytes (CNS or PNS?)

CNS, produces myelin sheath around CNS neurons

Microglia (CNS or PNS?)

Protect CNS by engulfing and invading microbes, clear away debris

Ependymal(CNS or PMS?)

Line brain ventricles and central canal of spinal cord, forms and circulates spinal fluid

Myelination

insulate axon of neuron and speed of nerve impulse

Action Potential Polarized

positive on outside, negative on inside

Action Potential Depolarization

sodium rushes in, positive on inside, negative on outside, necessary to allow neuron to transmit action potential

Action Potential Repolarization

after sodium rushes in potassium channels open and diffuses out of axon restoring +on outside,

Action Potential Refractory Period

pumps excess sodium out and potassium in

All or none principle

If impulse is strong enough it conducts along entire length of neuron at same strength

White matter

myelinated

Gray matter

lack of myelin

Meninges

DAP, Dura is strongest

Cerebrospinal fluid functions

mechanical protection(shock absorbing) Chemical protection (environment for neural signaling) circulation (exchange of nutrients and waste products between blood and nervous tissue

Reflex Arc Receptor

distal end of sensory neuron

Reflex Arc Sensory Neuron

conducts impulses from the receptor to spinal cord

Reflex Arc Integrating Center

interprets info from the sensory neuron and initiates a appropriate response

Reflex Arc Motor Neurons

relay nerve impulse to part of body that will respond

Reflex Arc Effector

part of body that responds

Brain Stem functions

heart rate and breathing, connects brain to spinal cord, made up by MPM

Diencephalon

Thalamus (principle relay station between various sections of brain) and Hypothalamus (main regulator of homeostasis, thirst hunger, sleep patterns, sex drive and maturation, helps move food)

Cerebrum lobes

frontal, temporal, parietal, occipital

Frontal lobe

control movement of voluntary skeletal muscles, intellectual processing, problem solving, concentration, memory

Parietal Lobe

interpret sensations, understand speech, use words to express thoughts and feelings

Temporal Lobe

hearing and balance, interpret sensory experiences, visual scenes, music, smells and complex sensory patterns

Occipital Lobe

visual processing and interpretation, combine visual images with sensory experiences

Cerebellum

inferior/posterior aspects of cranial cavity

Alzheimer’s

demential due to atrophy on heurons of frontal and occipital lobes

ALS

Lou Gehrig’s disease, muscular weakness and atrophy due to degeneration of motor meurons of spinal cord, medulla and cortex, no known cure

Bacterial Meningitis

inflammation of the meninges surrounding brain and spinal cord

Cerebral Palsy

motor disease due to loss of muscle control caused by damage to motor areas of brain during fetal age through infancy, irreversible though not progressive

Epilepsy

Short, recurrent, periodic attacks of motor, sensory or psychological malfunction, seizures

Multiple Sclerosis (MS)

destruction of myelin sheaths of neurons of CNS, no known cure

Parkinson’s

Characterized by fine slow spreading tremor, progressive disorder of CNS

Cerebral Vascular Accident

Stroke

Conjunctiva

Mucous membranes of eye

Lacrimal Apparatus

secretes tears

Extrinsic Muscles

move eyeball

Fibrous Tunic (what does it contain)-

outermost layer of eye, Sclera and Cornea

Sclera

posterior “white portion”, in fibrous tunic

Cornea

anterior transparent portion, bulges outward slightly

Vascular Tunic(what does it contain)

extremely vascular, contains choroid, ciliary body, iris and lens

Choroid

posterior, thin dark brown, lines inside of sclera

Ciliary Body

smooth muscles attaches to lens by ligaments and change thickness/shape of lens

Iris

colored part of eye, contraction of its smooth muscle dilate or constrict the pupils

Lens

special tissue that focuses and directs light entering the eye

Nervous Tunic (what does it contain)

inner layer, retina, optic nerve