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

Afferent Neurons (sensory)- conduct nerve impulses from sensory receptors to CNS

Efferent Neurons (motor) - conduct nerve impulses from CNS to muscles and glands

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

Schwann Cells (CNS or PNS?) - Produce myelin sheaths around PNS neurons

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, - on inside

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 - slurred speech, loss or blurred vision, dizziness

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

Retina - thin fragile layer of neurons that form the inner lining of eyes posterior wall

Optic Nerve - Transmits images to occipital lobe for interpretation

Ears function - hearing, balance and equilibrium

Outer ear - Auricle, auditory canal (extends into temporal bone)

Middle Ear parts - Typanic Cavity, auditory ossicles, Auditory tube, Tympanic Membrane

Tympanic cavity - contains auditory ossicles

Auditory ossicles - smallest bones in body, takes transmitted sound waves from tympanic membrane

Auditory(Eustachian) Tube 0 tube from muddle ear to pharynx allowing for pressure equalization

Tympanic Membrane(Eardrum) - separated outer from middle ear, vibrates from sound waves and transmits to auditory ossicles

Inner Ear parts- semicircular canals, vestibule, cochlea

Semicircular canals - three tiny fluid filled tubes that maintain balance

Vestibule - maintains balance by detecting position and motion

Cochlea - contains organ of corti, shape resembles snail shell, releases neurotransmitters

Myopia - nearsightedness, image focused in front of retina

Hyperopia - farsightedness, image focused in back of retina

Presbyopia - defect in vision in older age, resulting in farsightedness, loss of elasticity of lens due to advancing age

Cataracts - Abnormal loss of transparency of lens, vision becomes blurry/cloudy

Conjunctivitis - pink eye, inflammation of the conjunctiva

Strabismus - cross eyed

Glaucoma - intraocular pressure in eye resulting in atrophy of optic nerve

Macular Degeneration - destruction or tearing away of retina from back of eye

Vertigo - dizziness and spacial disorientation

Tinnitus - ringing or tinking sound/sensation in ear

Middle Ear Infection - infection of tympatic membrane

Deafness - loss of hearing conductive and sensual orientation deafness

How many spinal nerves? - 31 pairs

Satellite cells -

Medulla Oblongata - most inferior respiratory center, cardiovascular center

Pons - superior to M.O. - helps control respiration

Midbrain - superior to pons, connect the brain stem to diencephalon

Bony labyrinth - consists of vestibule, membranous labyrinth, semicircular canals, and cochlea

Membranous labyrinth - inside bony labyrinth, contains receptors for hearing and balance

Ametropia - refractive error in the eye, which causes blurred vision. It includes conditions such as myopia (nearsightedness), hyperopia (farsightedness), and astigmatism.

Sensorineural deafness - deafness resulting from damage to nerves or Organ of Corti

Mechanoreceptors - sensory receptors sensitive to touch, sound and motion

The two types of photoreceptors - rods and cones

Where are photoreceptors located in eye - retina

Receptor that detects black and white and outines objects - rods

Receptors that detect color vision and detains of objects - cones

How do impulses travel from eyes to the brain - traveling along optic nerve

Outermost white fibrous tunic of eye - Sclera

Acetycholine - neurotransmitter that controls the somatic nervous system