Chapter 2 Autonomic Nervous System Exam 2

SNS Functions

"fight or flight"/ move stored energy into movement/ i.e Smooth Muscle: gastrointestinal: directs blood flow away from intestines to skeletal muscle Cardiac Muscle: heart output of blood: heart pushes an increased amount of blood out to skeletal muscle Glands: Sweat Glands: secret sweat to cool down body so it can increase body movement

PNS Functions

"rest and digest"/ causes changes in homeostasis/ i.e. Smooth: Gastro: when activated increased blood flow to intestines Cardiac: Heart blood output: when activated blood output is decreased and activities that are low impact Glands: Salivitory: help break down food. low impact

Steps in Auditory Transduction

-Key Aspect- bending of cilia changes K+ permeability -Bending in one direction increases permeabilty but in the other direction decreases permeability -thus, direction of bending determines excitation of inhibition of a single hair cell

For the excitation of photoreceptors; there must be

-a chemical transformation by light -light isomerizes 11 cis retinal to 11 trans retinal -11 cis retinal has to be regenerated *requires vitamin A -metarhodopsin 11 activates transducin, a G- Protein -Hyperpolarization decreases releases of glutamate from the synaptic terminal of the photoreceptors -the net effect of reduced glutamate depends on the type of receptor it binds to on the post synaptic neuron

Amphetamine Action

-amphetamines are shaped like dopamine and imitate dopamine in the neuron -amphetamines bind to dopamine receptors, initiating the same response as dopamine -the compete with dopamine at cellular transporters causing dopamine to remain outside the cell longer

Opiate Action

-an opiate binds to an opiate-receptor on the presynaptic neuron -opiate binding initiates a cascade of neurochemical activity -the activity signals a massive efflux of dopamine into the synaptic cleft

Steps in Auditory introductions [in depth]

-auditory hair cells are mechanoreceptors -base sits on an elastic basilar membrane -vibration of the organ of Corti causes the base to vibrate and the cilia to bend -bending causes a change in K+permeability -bending in one direction causes depolarization and the other hyperpolarization -depolarization opens voltage gated Ca2+ channels -Ca2+ influx causes release of glutamate, which excites the afferent cochlear neuron that sends signal to the CNS

Olfaction

-chemical molecules (odarants) are vaporized in gas phase (air) -binding to specific olfactory receptors activates a G-Protein that is coupled to adenylyl cyclase, increasing cAMP -cAMP- sensitive cation channels (permeable to K+, Na+ and Cl-) open, depolarizing olfactory receptor triggerin gan AP in neurons of the olfactory nerve

Olfactory Receptors

-extremly diverse -at least 1000, each encoded by a different gene -one receptor per cell -some are more selective than others -CNS interprets combinations of stimuli to detect the resulting "smell"

In reference to the coding of intensity, give some details on how the frequency of Axon Potentials (firing rate) affects the coding

-intensity of stimulus encoded in the # of aps produced -receptor potential is a diret function of strength of stimulus -assuming the threshold potential is reached, the"stornger" the receptor potential, the more the action potentials are fired - the more frequent the APs, the more NT is released at the terminus of the nerve

Describe Mechanisms of Action

-opiod receptors are coupled with inhibitory G-proteins and their activation has a number of actions: 1) closing of voltage sensitive calcium channels 2) stimulation fo potassium efflux leading to hyperpolarization and reduced cyclic adenosine monophosphate (cAMP) production 3) OVERALL, the effect is a reduction in neural excitability reduced transmission of nociceptive impuleses

Rhodopsin Composition

-rhodopsin is a photosensitive pigment that is composed of the protein opsin and retinal - photons of light convert cis-retinal and trans-retinal -a series of conformational changes in rhodopsin activate a G-protein

Conceptual Steps in Hearing

-sound is focused by physical arrangment of the ear -sound energy is amplified within the ear through mechanical forces -individual hair cells are sensitive to sounds of a specific frequency -combinatorial effects of different hair cells determine perception of sound

Hearing

-transduces sound waves

In sympathetic NS pre-post synapses occur in one of two places:

1) sympathetic chian (paravertebral ganglia) 2) prevertebral ganglia

What is the first step that take place once a stimulus activates a sensory receptor?

1) the environmental stimulus interacts with the sensory receptor and causes a change in its properties. A mechanical stimulus causes movement of the mechanoreceptor. Photons of light are absorbed by photoreceptors causing photoisomerization of rhodopsin. chemical stimulants rxt with chemorecpetors which activates g proteins and adenylyl cyclase. a change occurs in the sensory receptor

List some qualities that are specific to the Neuroeffector Junctions

1)diffuse rather than discrete nerve-effector juncitons 2)single neurons branch to release NT across effector tissue 3)NT receptors on the effector are broadly distributed 4)no specialized region on effector, unlike at somatic motor end plate 5) effector can have both sympathetic and parasympathetic innervation

List the steps in transmitting sensory information

1)sensory receptors 2) first-order sensory afferent neurons 3)second-order sensory afferent neurons 4) third-order sensory afferent neurons 5) fourth order sensory afferent neurons

How is intensity encoded?

3 ways. 1) by the number of receptors that are activated (large # of stimuli will increase larger responses) 2) differences in firing rates of sensory neurons in pathway 3) activating different types of receptors i.e a light touch on skin may activate only mechanoreceptors whereas an intense damaging stimuli to the skin may activate mechanoreceptors and nociceptors the stimuli would be ditected as stronger but not as a different modality

How many taste buds do people have and how many cells does each taste bud consist of?

5-10 thousand taste buds made up of 50/100 cells

Adrenergic uses what type of NT? Cholinergic

A: epinephrine & norepinephrine C: ACh

In parasympathetic NS what is the main NT?

ACh is the main NT but some cases it may be something else i.e. nitric oxide

In SNS what NTs are used?

ACh is used in pre-ganglionic Norepinephrine is used at post ganglion-effector junctions

Describe how afferent and efferent nerves work

Afferent nerves bring information from the root ganglion into the spinal cord where Efferent nerves take information from the spinal cord and meets back at the root ganglion

Why is smell the strongest sense of memory?

Brain Anatomy; olfactory bulb has direct connections to limbic system, responsible for memory and emotion; no relay to the thalamus [other senses do not pass through this area of the brain]

During a sympathetic response how are your adrenal glands activated?

By a hormone to release epinephrine and norepinephrine (aka adrenalin)

Cholinergic uses what type of response? Adrenergic?

C: rest and digest A: fight or flight

What type of receptors are used in adrenergic vs cholinergic

Cholinergic uses muscaritnic and nicotinic Adrenergic uses alpha and beta receptors

What two different pathways do the Somatosensory System use?

Dorsal Column: fine touch, pressure, vibration, propriception Anterolateral System: pain, temp, light touch

What are the proteins ENaC and TRP Channels

ENaC: epithelial sodium channels TRP Channels: transient receptor potential channels

Name and describe the autonomic control centers in the brain

Hypothalamus: water balance, temp, hunger Pons: respiration Medulla: respiration, cardiac, vomiting, swallowing

human ears can detect within a range of what?

Hz-----20-20,000htz

What is being detected if a mechanoreceptor is changing rapidly vs slowly?

If moving rapidly there will be a detection of changes in velocity vs slowly will detect changes to intensity and duration of the stimuli

What is the third and final step that takes place once a stimulus activates a sensory receptor?

If the receptor potential is depolarizing it moves the membrane inward toward the threshold and increases the likelyhood that an action potential will occur. If hyperpolarization is occuring the opposite effect happens

Why are whiskers a great example of mechanoreceptors?

In each whisker follicle, mechanoreceptors respond specifically to rotation of the follicle by its muscles or to deflection of the whisker shaft by external contacts, both of which encode information about the direction, velocity and duration of displacements and torques.

In the somatic nervous system where is the cell body of the motoneuron located?

In the central nervous system (CNS), in either the brain stem or spinal cord, and its axon synapses directly on skeletal muscle, the effect organ.

When ACh is released into the synaptic cleft what happens.

It binds to the sodium channel recpetors and lets the channel know its time to open and there will be an influx of Na+ into the muscle cell. Once the membrane is depolarized enough Ca+ will enter and have voltage gated calcium release.

Name the five types of receptors

Mechanoreceptors Photoreceptors chemoreceptors thermoreceptors nociceptros

List the symptoms of Cholinergic Toxidrome (muscarinic/nicotinic)

Mus: salivation, lacrimation, urination, defecation, gi crmaping, emesis (vomitting) Nic: muscle cramps, tachycardia, weakness, twitching, fasciculations

What are the two types of ACh receptors? How do they differ?

Nicotinic: ligand-gated ion channels that mediate a fast synaptic transmission of the neurotransmitter Muscarinic: G-protein coupled receptors (GPCRs) that mediate a slow metabolic response via second messenger cascades

Give and example using bladder control pertaining to PNS and SNS

PNS: emptying requires simultaneous contraction of wall and relaxation of internal sphincter SNS: filling requires simultaneous relaxation of wall and contraction of internal sphincter (autonomic)

PNS Movement

PSN: carries information through long axons to ganglion that then rxt with short axon to target cell SNS: short axon rxts with ganglion synapsis then has a long axon directly to the target cell

List the two divisions the Visceral Motor is broken into

Parasympathtic & Sympathetic

Muscarinic ACh Receptors

Produces parasympathetic nerve effects in the heart, smooth muscle and glands G-protein couples receptors (receptors influence ion channels by mean of G-Protein)

Which specific opsins determines wavelength sensitivity

R, G or B

Damaged skin releases what and how does the body react to that symptom?

Releases a vairety of chemicals including bradykinin, prostaglandins, seratonin, substance P, K+, H+, this initiates an inflamitory response. The blood vessels become permeable and as a result there is local edema and redness of the skin. [Mast cells near the cite release histamine, which directly activates nociceptors. in addition, axons of the nociceptors to stimuli that were not previously noxious or painful]

Sensory (affarent) Division:

Somatic & Visceral Sensory

Motor (efferent) Division

Somatic Motor & Visceral Motor

Where is the Autonomic Nervous System located?

Spinal Cord: SNS(middle of spinal cord; thoracic and lumbar) PNS(top or bottom of the spinal cord; brain stem and saccral)

Dopamine

The High: morphines activation of the opiod receptor in neurons of the nucleus accumbens in the brain 1) reigns in the release of the neurotransmitter y-aminobutyric acid (GABA) 2) this drop in GABA(amino acid/ most common inhibitory) causes a neighboring cell to expel dopamine 3) in turn elicits the euphoria associated with opiods

Describe the process of the Autonomic Nervous System

The cell body of each preganglionic neurons resides in the CNS. The axons of the preganlionic neuron synapse on the cell bodies of the postganglionic neurons in one of several autonomic ganglia located outside the CNS. The axons of the posts ganlionic neurons then travel to the periphery, where the synapse on visceral effector organs such as heart, bronchioles, vascular smooth muscle, gastrointestinal tract, bladder, and genitalia.

What is the third division of the autonomic nervous system? Where is it located?

The enteric nervous system and it is located in the plexuses of the gastrointestinal tract.

Describe the process of the somatic nervous system.

The neurotransmitter acetylcholine (ACh) is released from presynaptic terminals of the motorneurons and activates nicotininc receptors located on the motor end plates of the skeletal muscle. An action potential in the motoneuron causes an action potential in the muscle fiber, which causes the muscle to contract.

How are tonic receptors illustrated? Phasic?

Tonic: mechanoreceptors Phasic: pacinian corpuscles

Brain Stem

a collaboration of the medulla, pons, and midbrain. 10 of the 12 cranial nerves arise in the brainstem (carry sensory info to the brain and motor info away from it)

What two neurons do the autonomic pathways consist of?

a preganglionic neuron: originates in the brainstem or the spinal cord a postganglionic neuron: lies outside the central nervous system in collections of nerve cells

parasympatholytic

a substance or activity that reduces the activity of the parasympathetic nervous system. (The parasympathetic nervous system is often colloquially described as the "Rest and Digest" portion of the autonomic nervous system.)

Somatic Nervous System

a voluntary motor system under conscious control. Each pathway consist of a single motoneuron and the skeletal fibers it innervates.

What is the target tissue for a1, a2, B, B2, Nicotinic, and Muscarininc receptors?

a1: vascular smooth muscle, skin, renal, and splanchnic Gastro tract, sphincters bladder, sphincter Radial muscle, iris a2: gastro tract, wall Presynaptic adrenergic neurons B1: heart, salivary glands, adipose tissue, kidney B2: vascular smooth muscle of skeletal muscle, GI tract, wall bladder, wall bronchioles Nicotinic: skeletal muscle, motor end plate (N1), postganglionic neurons, SNS&PNS, adrenal medula Muscarinic: all effector organs, PNS sweat glands, SNS

Gate Control Theory of Pain

activation felt even though non-painful fibers (Aa) sends inhibitory signals to nonciceptive afferents travelin gto the CNS

Phasic Receptors

adapt rapidly to stimuli, produce APs in response to change, intial burst of APs followed by a rapid decline, allows body to ignore constant unimportant stimuli (bad smell)

Tonic Receptors

adapt slowly to stimuli, produce a constant rate of APs as long as a stimuli is present, monitors things that are continually sensed (body position)

At what point do sensory receptors "adapt" to stimuli?

adaptation occurs in receptors when a constant stimuli is applied for a period of time. When the frequency of APs declines although the stimulus continues (smell, pressure, touch adapt quickly)

Nicotinic ACh Receptors

all autonomic ganglia all neuromuscular junctions some CNS pathways

In light how do you define amplitude and wavelength

amplitude: percieved as brightness; up and down length of wave from bottom to top wavelength: (nm) perceived as hue; length of wave from left to right

what is sensory transduction

an environmental stimulis (pressure, light, chemicals) activates a receptor and is converted into electrical energy

Autonomic Nervous System

an involuntary system that controls and modulates the functions primarily of visceral organs. (the internal organs of the body, specifically those within the chest (as the heart or lungs) or abdomen (as the liver, pancreas or intestines). In a figurative sense, something "visceral" is felt "deep down." It is a "gut feeling.")

Neuroeffector Junctions

analogous to the neuromuscular junctions of the somatic nervouse system

retina

area in the back of the eye containin gphotoreceptors

pupil

arperture of the eye

Cerebellum

attatched to brainstem, coordinate movement, planning and execution of movement, maintenance of posture and coordination of head and eye movements

Kidneys are closer to chest or back

back

Beural Anatomy; Interneurons

bipolar cells, horizontal cells, amacrine cells

How is arterial blood pressure sensed?

by baroreceptors located in the walls of the carotid sinus. The information is transmitted, via the glossophyrangeal nerve, to the vasomotor center in the medulla of the brain stem- in the medulla the sensed blood pressure is compared with a set point, and the medullary vasomotor center directs changes in sympathetic and parasympathetic outflow to the heart and blood vessels, which produce appropriate adjustments in arterial pressure.

Affarent Nerves

carry information into the central nervous system

Efferent Nerves

carry information out of the nervous system

accommodation (in reference to the eye)

changing the shape of the lense to focus images on the retina caused by contracting/relaxing ciliary muscles (lens falttens when focusing on distant objects and becomes rounder for focusing on close objects.

Neural Anatomy; Pigment Epithelium

contains melanin to absorbs excess light; stores vitamin A

List Functions of Parasympathetic NS

contracts pupil, stimulates salivation, inhibits heart, constricts bronchi, stimulates digestive activity, stilumlates gallbladder, relaxes rectum

iris

controls diameter of the pupil -contraction of sphincter muscles; miosis -contraction of radial muscles; mydriasis

Neuropathic Pain

damage to A or C fibers may increase sensitivity or cause spontaneous AP firing

Primary Hyperalgesia

damaged tissue has increases sensitivity to pain -reduced threshold to pain (increased intensity of sensatino, spontaneous pain)

intensity is a function of pressure, how is it measured?

decibels

Receptive Fields

defines an area of the body that when stimulated results in a change in firing rate of a sensory neuron

lens

dense high protein structure that adjusts optical focus, focus adjusted by process called; accommodation -at rest, zonal fibers suspend lens and keep it flat (distant) -contraction of ciliary muscles releases tension in zonal fibers; lens gets more round/near objects

List Functions of Sympathetic NS

dilates pupils, inhibits salivation, relaxes bronchi, accelerates heart, inhibits digestin, stimulates glucose release by liver, secretion of epinephrine from the kidney, relaxes bladder, contracts rectum

Concerning balancing functions what allows precise control of tone and activity i.e. heart rate

dual innervation: most organs of the body by the sympathetic (on the left) and parasympathetic (on the right) divisions of the ANS

Somatic nervous system has direct innervation from CNS to __________?

effector tissue

nociceptors

extremes of pain and temp (skin) activated by extremes of pressure, temperature, or noxious chemicals

presbyopia

farsightedness that occurs naturally with age as the lens becomes less flexible

Thermoreceptors

free ending nerves with high thermal sensitivity, temp changes activates family of ion channels on the receptor membrane= TRP (transient receptor protential) channels, each TRP channel has a unique temp threshold

vitreous humor

gel of extracellular fluid containing collagen

cones

higher threshold for light, provide higher visual acuity, responsible for color vision

receptor potential

increases or decreases the likelihood that action potentials will occur

What does cocaine to do the body?

it blocks dopamine transporters so there can be no reuptake of dopamine and the dopamine receptors can continually bind to dopamine until there is none left becuase there will be no reuptake or distirbution of those molecules

If the receptive field has a higher order of the CNS neuron, will the receptive field be more/less complex? why/why not?

it will be more complex due to more neurons converge in relay nuclei at each level. ie the first order of sensory neurons have the simplist receptive field/ the fourth order sensory neurons have the most complex receptive fields

where is the location of the primary auditory cortex

lacated bilaterally, near outersurface of brain

hypothalamus

lies ventral to the thalamus, contains center that regulates body temp, food intake, water imbalance

location of the primary visual cortex

located bilaterally at lower back of brain

How is location of the stimulus perceived and conveyed in the brain?

location is endcoded by a receptive field of sensory neurons and my be enhanced by lateral inhibition. By receptive fields

Sound

longitudinal wave, meaning that the motion of particles is along the direction of propagation

rods

low threshold of response to light, sensitive to low intensity light, don tparticipate in color vision

If a receptive field is smaller will the the sensation be more general or more defined

more defined/localized/identified

Spinal Cord

most caudal portion of the CNS extedning from the base of the skull to the first lumbar vertebra. 31 pairs of spinal nerves, sensory(afferent) and motor (efferent).

General Inclusions in Somatic Motor

motor innervation of all skeletal muscles (except pharyngeal arch muscles)

General inclusions in Visceral Motor

motor innervation of smooth muscle, cardiac muscle, and glands; equivalent to autonomic nervous system (ANS)

location of thalamus

near the center midline of the brain

myopia

nearsightedness caused by inability to flatten the lens enough to focus image on retina

retina

neural portion that transduces light into electrical signals that pass down the optic nerve optic nerve exists at optic disc. devoid photoreceptors:blind spot fovea; point on the retina that has maximal vision acuity

Nociceptors have two major classes

non adapting receptor classes are mechanical nociceptors: finely mylenated A-delta afferent nerve fibers and respond to sharp, pricking pain polymodal nociceptors: hot and cold stimuli response

chemoreceptors

olfaction (olfactory mucous) taste (tongue) Arterial Po2 (carotid/aoritc bodies) pH of CSF (ventrolateral medulla) activated by chemicals / involved in detection of oxygen and CD in the control of breathing

Where ddoes the adrenal gland sit? Why is this position interesting?

on top of the kidney, there is a synapse in the gland that can cause a body-wide release of epinephrine

How many types of sensations do nerve fibers transmit?

one

Cornea

outer covering of the eye where light is first focused

Neural Anatomy; Ganglion Cells

output cells of retina project via optic nerve

Phantom Limb Pain

pain felt even though nonciceptors no longer present in missing limb -peripheral sesitization:s an increased sensitivity to an afferent nerve stimuli. -somatosensory reorgnization: children with spastic cerebral palsy: a multimodal neuroimaging study.

rhodopsin

phototsensitive pigment (composed of opsin[protein member G-protein receptor family] and retinal [an aldehyde form of vitamin A])

Where are pre/post ganglionic neurons located>

pre (the neuron proximal to the ganglion) post( the neuron distal to the ganglion)

Thalamus

processes almost all sensory info going to the cerebral cortex and almost all motor information coming from the cerebral cortex to the brainstem and spinal cord

Somatosensory System

processes info about touch, pain and temp using mechanoreceptors, thermoreceptors and nociceptors

How does a phasic receptor respond to an onset of stimuli?

receptor returns quickly to baseline, here the receptor potential remains depolarized for a longer portion of the stimulus period, and the action potentials continue. Once receptor potential begins to repolarize, the rate of action potentials declines and there is silence

How does a tonic receptor respond to an onset of stimuli?

responds to an onset of stimuli with a depolarizing receptor potential that brings the membrane to threshold, resulting in a long series of action potentials

What do both rods and cones contain?

rhodopsin

choroid

rich in blood vessels and supports the retina

medulla

rostal extension of the spinal cord, autonomic centers regulate breathing, blood pressure, coordinate swallowing, coughing and vomiting reflexes

pons

rostral to medulla, helps with balance and maintenance of posture, regulating breathing, relays info from the cerebral hemispheres to the cerebellum

midbrain

rostral to pons, helps with eye movement, contains relay nuclei of the auditory and visual systems

What is the name of the resivore inside our muscle cells that releases calcium for our disposal?

sarcoplasmic reticulum

Visual Receptive Fields

see slide 17 of 41

What features can be encoded?

sensory modality, spatial location, frequency, intensity, threshold, and duration of stimulus

Preganglionic fibers are ....... postganglionic fibers are.......

short long

a pure tone

sinsusodial wave of a signle frequency; most sounds are a mixture of different tones

Be able to draw light conversion of retinal from a cis- to a trans-configuration

slide 21 of 41

The motor nervous system has two components:

somatic and autonomic

Thalamus Details

sorts our all sensory info, compares input and determines what info is worth sending to cortex, body ignores most sensory info, example ac uni, compares info from the right and left eyes for stereotypic vision, and left ear to determine direction of sound

General inclusions in Visceral Sensory Nerves

stretch, pain, temperature, chemical changes, and irritation in viscera, nasusea and hunger (special: taste)

thermoreceptors

temperature (skin) activated by temp or changes in temp

receptive field

the area of the body that, when stimulated, produces activity in a neuron

What system controls most moment-to-moment physiological functions?

the autonomic system

if skin temp rises to damaging levels (above 45dC) what happens to warm receptors?

the become inactive

What does the CNS include?

the brain and spinal cord

What is the second step that takes place once a stimulus activates a sensory receptor?

the changes cause ion chanels in the sensory receptor membrane to open or close, which results in a change in current flow. If ionic current flow moves inward (positive charges move in receptor cell) then depolarization occurs. If current moves outward (positive charges leave the cell) then hyperpolarization occurs. This change is called the receptor potential/generator potential

If skin is wamred above 36 degree C which receptor will become quiescent

the cold

What determines the frequency tune>?

the location of the hair cell along the length of the basilar membrane; the bsilar membrane gets thinner and more flexible toward the center of the cochlea.

Diencephalon

the place between the brain made up of the thalamus and hypothalamus

The Brain-Body Connection

the portion of the nervous system that controls the visceral functions of the body and continually adapts the function of the internal organs, skin and viscera to internal and external stimuli

Encoding

the relative elasticity of the basilar membrane alon gits length determines the frequency required to

Neurotransmitters

the relay of information between neurons and their target cells at chemical synapses. Catagorized by amino acids, peptides, monoamins

The autonomic nervous system has two major divisions:

the sympathetic: the parasympathetic:

How is the stypes of sensation (sound, smell, etc) perceived?

the type of sensation percieved is determined by where the fiber synapses in the CNS

If the skin is cooled below 36 degree C what receptors will become quiescent

the warm

Nociceptors

thermal, chemical, and mechanical receptors that respond to noxious stimuli that can produce tissue damage, respond to a diverse group of stimuli, wide varitey of ion channels enables this diversity in response

cones are more location specific because

they are derived from mulitple ganglion and bipolar cells

Rods are less accurate because

they are derived from one ganlion cell

How do the somatic and autonomic nervous systems distinguished?

they are distinguished by the types of effector organs they innervate and the types of functions they control

Stimulus modality is often encoded by labeled lines, what are they?

they are pathways of sensory neurons dedicated to that modality. i.e the pathway of neurons dedicated to vision begin with photoreceptors in the retina

What do all preganglionic neurons of the autonomic nervous system release?

they release ACh

What do all postganglionic neurons of the autonomic nervous system release?

they release either ACh or norepinephrine (hormone that is released by the adrenal medulla and by the sympathetic nerves and functions as a neurotransmitter. It is also used as a drug to raise blood pressure.), or in some cases, neuropeptides (any of a group of compounds that act as neurotransmitters and are short-chain polypeptides.)

Mechanorecpetors

touch(skin) audition(organ of Corti) vestibular (macula) activated by pressure or changes in pressure

General inclusions in Somatic Sensory Nerves

touch, pain, pressure vibratio, temp, and propioception in skin, body wall and limbs (special: hearing, vision, smell)

Neural Anatomy; Photoreceptors

transduce light energy into electrical energy (rods and cones)

Mechanoreceptors

transform mechanical stimuli into electrical signals, all organsisms and most cells sense and respond to mechanical stimuli, two main types of proteins ENaC&TRP channels, channels are linked to extracellular matrix, mechanical stimuli alter channel permeability

Light

transverse waves, moving perpendicular to the direction of propagation; an electromagnetic wave

What is the difference in have two cones and three cones?

two cones can not see the color red

Photoreceptors

two types: rods and cones * both transduce light energy into electrical energy

In sensory transduction what does the conversion typically involve?

typically it will involve the opening or closing of ion channels in the receptor membrane, which leads to the flow of ions (current flow) across the membrane; leads to change in membrane potential i.e receptor potential

Five types of taste receptors

umami, fat, salty, sweet, sour, bitter

photoreceptors

vision (retina) activated by light

sound frequency

wave cycles per second, mearsured in hertz

sound waves

waves of compression and decompression

When does sensory coding beign?

when the stimulus is tranduced by senseory receptors and continues as the information is transmitted to progressively higher levels of the CNS

When your sympatheitc nervous system is activated what happens?

your pupils dilate, your salivary gland decreases in secretion, your respiratory rate will increase, your heart rate increase (i.e better oxygenation), the liver secrets sugar, the adrenal glands are activated