Peripheral Nervous System

what does the peripheral nervous system control?

acts as the communication network, carrying messages to the brain (sensory input) and from the brain

Subdivisions of the peripheral nervous system

Somatic and Autonomic

What does the somatic system regulate?

skin and skeletal muscles

What does the somatic system control?

voluntary response

What does the somatic system include?

reflexes

What does the somatic system protect the body from?

harm

What does the autonomic system regulate?

cardiac and smooth muscles and glands

does the autonomic system function automatically?

yes meaning that it is involuntary

What are the subdivisions of the autonomic system?

sympathetic and parasympathetic

What does the sympathetic system control?

emergency situations

whats the response to emergency situations?

increases heart rate and respiration, digestion, excretion inhibited, pupils dialted

what is the neurotransmitter for the sympathetic system?

norepinephrine

what is norepinephrine similar to?

adrenaline

what does the parasympathetic system respond during?

relaxation

how does the parasympathetic system response?

digestion, regular heart rate, pupils contracted

what is the neurotransmitter for the parasympathetic system?

acetycholine

What are the types of neurons?

sensory, interneuron, motor neuron

what does the sensory neuron do?

receive info from outside, takes it to CNS

what are sensory neurons a part of?

PNS and afferent pathway

what does the interneuron do?

coordinates info and determines response?

what are the interneurons a part of?

CNS

What does the motor neuron do?

causes response

what is the motor neuron a part of?

PNS and efferent pathway

what do dendrites do?

receive neurotransmitter

what is the soma?

the cell body

what is located inside the soma?

the nucleus

what does the axon do?

sends neurotransmitters away to next neuron

what are the nodes of ranvier?

the periodic gaps along the axon (no myelin)

what do the nodes of ranvier allow for?

rapid conduction of nerve impulses

what is the synapse?

space in between 2 neurons

what does the synapse allow for?

allows for instantaneous communication throughout body

What neurotransmitter does the motor neuron release?

ACh

what is the function of the retina?

absorbs light, prevents it from scattering, and removes dead cells

What does the olfactory epithelium allow for?

smell

what is the function of the cochlea?

hearing

what are papillae?

peg like projections

what are nerve impulses necessary for?

all functions of the nervous system

what do impulses travel through?

nerve networks

what causes nerve impulses?

bioelectric currents

what are bioelectric currents?

movement of Na+, K+, Ca+2, Cl-

what happens to axons during resting potential?

they are polarized

what does it mean if an axon is polarized?

outside of axon is +, inside is -

What keeps an axon in resting state?

uneven distribution of charges

what must occur to conduct a nerve impulse?

action potential

what happens during action potential?

the polarity inside the axon changes from negative to positive

what is depolarization?

the inside of the axon becoming positively charged

what happens after depolarization?

the inside of the axon quickly become negative again

what is repolarization?

when the inside of the axon quickly become negative again

what kind of response is action potential?

an all or nothing response (once it begins, it will complete)

what does the intensity of the message depend on?

the frequency of the action potentials

what dose the speed of the message depend on?

the diameter of axon and if the axon is myelinated

where are neurotransmitters stored?

axon terminals

what are axon terminals?

when the axon branches at the end

what is the first step of nerve impulse transmission?

terminals release neurotransmitters across synapse

what is the second step of nerve impulse transmission?

neurotransmitters are received by the dendrites of the next neuron

what catches sound waves?

pinna

what is the pinna?

outer ear

where does sound travel through?

the auditory canal

what happens after sound travels through the auditory canal?

they hit the tympanic membrane

what is the simple term for the tympanic membrane?

ear drum

where is the tympanic membrane located?

in between canal and middle ear

what keeps the tympanic membrane taut?

muscles

why is the tympanic membrane kept taut?

because it allows for the membrane to vibrate when hit by sound wave

what conducts sound waves?

the cochlea

how does the cochlea conduct sound waves?

through fluids

what does the cochlea require to “push” sound waves?

more pressure

what generates the pressure needed by the cochlea?

the ossicles

what are the 3 ossicles?

malleus, incus, stapes

malleus?

hammer

incus?

anvil

stapes

stirrup

what pushes on the basilar membrane?

the stapes

what does the pushing of the stapes on the basilar membrane cause?

vibration in different locations

what does the cochlea have to do for the brain to understand the sound waves?

must convert physical sound waves into electrical signals

what structure contains 1000’s of tiny hairs?

organ of corti

where is the organ of corti found?

inside the cochlea

what is the cochlea made of?

3 separate coiled tubes separated by a thin membrane

what happen in the organ of corti when vibrations are strong enough?

the hairs move and send an electrical signal impulse to the vestibulocochlear nerve

what does the vestiulocochlear nerve transmit signals to?

the brain

how many of our sensory receptors are in the eye?

70%

How do eyelashes protect the eye?

the eyelashes protect the eye by protecting the border of each eyelid

what is pinkeye?

pink eye is the inflammation of the conjunctive

what are tears?

tears are the release of dilute salt solution onto the anterior surface of the eye ball through several small ducts

What is diplopia?

a condition where you see 2 images when looking at one object

what is the pupil?

tiny black circle of eye

what is the iris?

circle surrounding pupil that gives eye color

what is the sclera?

the white outer layer of the eyeball

what the conjunctiva?

the mucous membrane that covers the front of the eye and lines the inside of the eyelids.

whats the cornea?

the clear, dome-shaped outer layer at the front of your eye

what is conduction deafness

deafness that results when something interferes with the conduction of sound vibrations to the fluid of the inner ear

what is sensorineural deafness?

deafness causes by damage to the receptor cells in the auditor cortex, spiral organ or cochlear nerves

what are tastebuds

receptors that are scattered in the oral cavity

what are papillae

projections on the tongue that contain taste buds

5 properties of taste

sweet, salty, sour, bitter, umami

what are chemoreceptors?

receptors for smell or taste that respond to chemicals in solution

explain the roll of olfactory cilia

to transmit impulses when stimulated

what does smells associate with danger trigger?

sympathetic nervous system

define memory

storage and retrieval of information

what does the transfer of information from STM to LTM involve?

emotional state, rehearsal, association, and automatic memory

what are the crucial structures in the brain for storing memory?

temporal lobe and PFC