Exam 5 Flashcards
What are the 2 types of general senses?
*Receptors distributed over a large part of the body
Somatic - located in skin, muscle, joints
Visceral - located in internal organs
What are the 5 somatic senses?
Touch
Pressure
Proprioception
Temperature
Pain
What are the 5 special senses?
*Receptors localized within specific organs
Smell
Taste
Sight
Hearing
Balance
What are the 6 receptors in the skin?
Free nerve ending - pain,temp,itch, proprioception
Merkel disc - light touch/pressure
Hair follicle - light touch /bending of hair
Meissner corpusles - 2 point discrimination
Ruffini end organ - continous touch, pressure, stretch
Pacinian corpuscle - deep pressure vibration proprioception
Sensory neuron uses a how many neuron system?
Ascending
3 neuron
Primary: PNS -> posterior horn
Secondary: Decussate, Spinothalamic tract -> thalamus
Tertiary: Thalamus ->somatic sensory cortex
What are the 4 sensory tracts?
Spinothalamic
Dorsal-Column/Medial-leminscal
Trigeminothalamic
Spinocerebelalr
What does the spinothalamic tract sense?
Pain, temp, light touch, pressure, tickle, itch
What does the dorsal-column/medial lemniscal tract sense?
2 point discrimination, proprioception, pressure, vibration
What are the 2 nuclei in the dorsal column / medial lemniscal tract?
Fasciculus gracilis: inferior to midthoracic
Fasiciculus cuteatus: above midthoracic
What does the Trigeminothalamic tract sense?
what cranial nerve is involved?
Pain, temp, light touch, pressure, tickle, itch, 2 point discrimination for face, nasal cavity, oral cavity
Cranial nerve V - trigeminal nerve
What does the Spinocerebellar tract sense?
Unconscious proprioceptive info
Goes straight to cerebellum
Posterior and anterior tracts
What areas of the brain do our senses go to?
Somatic sensory cortex = posterior to central sulcus
Taste - inferior end of postcentral sulcu
Olfactory = frontal lobe
Auditory = temporal lobe
Visual = occipital lobe
What is Wernickes and brocas area and what do they do?
Wernickes area - Sensory speech - understanding what is heard
Brocas area - sending messages to muscles to make sound
What is Aphasia?
Absent or defective speech or language comphrension. Caused by a lesion
Skeletal neuron uses a how many neuron system?
Decsending
2 neuron pathway
Upper motor: Premotor cortex->interneurons connect to lower motor neurons
Lower motor: Anterior gray horn -> PNS-> Skeletal muscles
What areas of the brain do our motor come from?
Precentral gyrus - primary motor
Premotor area - (anterior to primary motor) - where our motor function are organized before initiation
Prefrontal area - Motivation, foresight to plan and initiate, emotional behavior mood
What are the 2 motor nerve tracts?
Direct (decessates in pyramids): Muscle tone, speed and precision of skilled movements
Indirect: less precise movements
What are the 2 direct pathways for descending motor neurons?
Corticospinal (lateral and anterior): Movements below head
Corticobulbar: movements of head and neck
What are the 3 indirect pathways for descending motor neurons?
Rubrospinal: Red nucleus, regulates fine motor of distal part of upper limb
Vestibulospinal: Exterior muscles in trunk and proximal lower limbs, maintains upright posture
Reticulospinal: Maintenance of posture
What is the cerebellar comparator function?
- Decide what we want to do in primary motor cortex
- Tells cerebellum what it wants to do along with lower motor neuron
- Proprioceptive signals from skeletal muscles and joints to cerebellum convey info about muscles being moved
- Cerebellum modifies info from motor cortex
What are the reflexes in brainstem?
Heart rate, blood pressure, respiration, sleep, swallowing, vomitting, coughing sneezing
also RAS
What is RAS?
Recieves input from Cranial nerves, ascending and descending pathways.
Wakefullness is maintained by info coming from eyes, ears and cerebral cortex
What are the 4 types of brainwaves?
Alpha: Resting state eyes closed
Beta: Intense mental activity
Theta: in adults with frustration or brain disorders, also in children
Delta: Deep sleep, infancy and severe brain disorders
A portion of the dorsal-column/medial lemniscal tract that carries proprioceptive sensations from the nerve endings in the feet and legs is called?
Fasciculus gracilis
Which color represents the primary motor and sensory part of the brain?
Purple - Motor
Yellow - Sensory
What is located in the postcentral gyrus of the parietal lobe?
Primary somatosensory cortex
What is the sequence of info flow in response to bitting into a slice of pizza?
Sensory receptor activated
Impulse sent to CNS
sensation
Perception
What are the differences between Somatic and autonomic systems?
Somatic
- things you can control
- Sensory: Touch, pain, temp, proprioception, special senses
- Motor: Skeletal muscles
-1 motor neuron, uses ACH and is myelinated
Autonomic
- Things you cant control
- Blood vessels, organs, glands
- 2 motor neurons, uses ACH for pregang and either ACH or NE at effector. 2nd is not myelinated
What are the 2 divisions of the ANS?
Sympthetic: Fight or flight (max use of energy in best way possible)
Parasympathetic: Rest and digest (calming down but ramping up digesting)
What is autonomic tone?
What is sympathetic tone?
What is parasympathetic tone?
normal background rate of activity that represents the balance of the 2 systems
- Keep BV partaially constricted to maintain BP. Excites heart but inhibits digestive and urinary functions
- Maintains smooth muscle tone in intestines and hold resting HR at 70-80 BPM. Slows heart and excites digestive and urinary functions. (does not work on BV)
What are the reflexes/nerves for Sympathetic and Parasympathetic divisions?
Sympathetic
-Cardiac accelerator - increase heartrate, Vasomotor
Parasympathetic
-Vagus - lowers heartrate, gastric/intestional, defecation/urination, swallowing, coughing, baroreceptor
Sympathetic Division
What is the AKA?
Where are the short and long nerves?
Pregang cell bodies are located where?
Nerves exit SC where?
Where do synpases happen?
Thoracolumbar
Short pregang myelinated via white, long post gang unmyelinated via gray (unless splanchnic)
pregang somas are located in lateral horn
Nerves exit SC T1-L2
Some synpases happen at sympathetic chain others at Prevertebral ganglia (Splanchnic nerves)
What are the 4 routes for the Sympathetic division?
- Synapse immediately with post gang
- Travel up or down Sympathetic chain and synapse at different levels
- Pass w/o synpasing and synapse at splanchnic nerve to prevertebral ganglion
- Pass w/o synapsing and synapse at splanchnic nerve to prevertebral ganglion to adrenal medulla (secretes NE & E into the blood stream to prolong effects of Sympathetic division, wide reaching effects)
*in white ramus out gray ramus
Parasympathetic Division
What is the AKA?
Where are the short and long nerves?
Pregang cell bodies are located where?
Nerves exit SC where?
Where do synpases happen?
Craniosacral divison
long pregang myelinated, short post gang unmyelinated
Cell bodies are located in 4 cranial nerves (Oculomotor III, Facial VII, Glossopharyngeal IX, Vagus X) and in lateral gray horn of sacral 2-4
Synapses happen in terminal ganglia or effector
Sympathetic division nerves neurotransmitter is what for
Preganglionic neuron?
Postganglionic neuron to most effector tissues?
Postganglionic neuron to mose sweat glands?
ACH
NE
ACH
What does a adreneric receptor release/accept?
Release / Accept Norepinephrine
Alpha - excitatory
Beta - inhibitory
What does a Cholinergic receptor release/accept?
What are the 2 types of cholinergic receptors?
Secrete ACH
Nicotinic - Pregang
& Muscarinic - Effector
How can different autonomic neurons have different effects?
By releasing different neurotransmitters and different types of receptors found on target cells
Why do the effects of Sympathetic last longer than Parasympathetic?
ACH released by parasympathetic is broken down quickly at synapse
NE by sympathetic is reabsorbed by nerve, diffuses into adjacent tissues and passes into blood stream (Also released by adrenal medulla which can prolong effects)
What are the autonomic effects on glandular secretion?
indirect result of their effect on blood vessels
Vasodilaion: increased blood flow = increased secretion
Vasoconstriction: decreased blood flow = decreased secretion
What is the Enteric nervous system?
Regulation of activity of digestive tract
Can operate on own but lets ANS know whats going on/ ANS can regulate as well
Autonomic neurons affect responses of smooth muscle and glands
What are some higher level influences of brain on ANS?
Cerebrum/limbic- thought and emotions
Hypothalamus - Interacts with cerebrum, limbic, brainstem, spinal cord, reg body temp
Brainstem - controling pupil size, tears, salivation, coughing, swallowing, digestive, HR, BV and respiration
Spinal cord - regulating defecation, urination, penile & clitoral erections and ejactulation
What is dual innervation?
When sympathetic and parasympatheic both go to the same effector
Usually have opposite effect
What is single innervation?
by adjusting the frequency of action potential
Name the receptors below
Orange - free nerve endings
Blue - Meissners corpuslce
Green - Ruffini end organ
Red - Pacinian corpuscle
Purple - Hair follicle
Yellow - Merkel disc
Collateral ganglia are unpaired ganglia located in the ______.
abdominopelvic cavity
What is the pathway for olfaction?
- Odorants come into nose and diffuse into the mucous where there are olfactory hairs.
- Odorants dissolve in muscous, bind to receptors on olfactory hairs which depolarizes cell and causes an action potential in olfactory neurons
- Goes through olfactory tract to primary olfactory cortex in temporal lobe
- Secondary destinations: hippocampus, amygdala, hypothalamus, insula, orbitofrontal cortex
*Olfactory epithelium replaced every 2 months
*One receptor may bind to more than one type of receptor
What are the 4 forms of papillae for taste?
Which one does not have taste buds?
Filiform - No taste buds
Vallate - largest, least numerous. V shape. most taste buds
Fungiform - mushroom
Foliate - on sides of tounge, most sensitive taste buds. Decrease with age
What odorants act on nociceotors of trigeminal nerve?
Ammonia, menthol, chlorine, capsaicin of hot peppers
What are the 5 tastes?
How often do taste buds replace?
Salty, Sweet, sour, bitter, umami
every 10 days
What is the neuronal pathway for taste?
Secondary receptor!!
- Tastant goes to taste pore and binds to taste hair
- Causes an inflow of neurotransmitter, release synaptic vesicles to neuron which generates AP on sensory neuron
- Pass through VII, IX, X and enter brainstem
- then enter nucleus of tractus solitarius then synapse to the thalamus
- From thalamus to insula
What is a thin transparent mucous membrane that lines eyelids and covers anterior surface of eyeball?
Conjunctiva
What are the 2 glands on your eyelashes?
Ciliary glands (modified sweat glands)
Meibomian glands - sebum
What are the 3 tunics of they eye? and what structures are in each?
- *Fibrous Tunic**
- Sclera: maintains shape, protects
- Cornea: avascular, bends and refracts light
- *Vascular Tunic**
- Iris: Controls light entering pupil
- Ciliary body: produces aqueous humor, control lens shape
- Choroid: associated with sclera, thin & pigmented
- *Retina**
- Pigmented retina - reduce light
- Sensory retina - rods & cones
Rods and cones are for what type of vision?
where are they found?
- *Rods**
- black & white vision, night vision.
- Found over most of retina except fovea. More sensitve to light than cones
- Rhodopsin-> opsin&retinal
- When not stimulated they are depolarized always sending a inhibtoyr signal, when light hits they hyperpolarize
- *Cones**
- Color vision and bright light
- Mainly in fovea and macula
- Iodopsin->blue, red, green
Where is the Anterior cavity and the posterior/Vitreous cavity?
Where are the anterior/posterior chambers?
Anterior cavity: Lens forward (aqueous humor)
Posterior cavity: lens backward (vitreous humor)
Anterior chamber: Iris to cornea
Posterior chamber: Lens to Iris
Where is aqueous humor made?
Ciliary body makes aqueous humor constantly
virtous stay relatively the same your whole life
What is glucoma>?
Increase in intraocular pressure
aqueous humor does not drain and fills up chambers putting pressure
What is the lens of the eye?
Held by suspensory ligaments
Changes shape
Produce proteins called crystallines
Transparent, biconvex
What is far point of vision and what is near point of vision?
Far point of vision: point which lens does not have to thicken. 20ft or more from eye
Near point of vision: point at which changes occur in lens, size of pupil and distance between pupils. Closer than 20ft
What is Emetropia?
Hyperopia?
Myopia?
Normal
Farsightedness - eye too short - focal point behind retina
Nearsightedness - eye to long - focal point in front of retina
In the sensory retina what are the 3 layers of neurons?
Rods & Cones synapse with Bipolar cells (first order neuron) which synapses with ganglion cells (second order neuron)
*Only rods and cones produce visual images
What does Rhodopsin do?
Absorb light
Bleaching when retinal dissociated from opsin
What is
Presbyopia?
Astigmatism?
Retinal detachment?
Cataract?
Macular degeneration?
Diabetes?
Presbyopia - age related loss of abiliy to focus/lens unflexible
Astigmatism - cornea or lens not unifromly curved
retinal detachment -
Cataract - Lens fibers darken or get cloudy with age, fluid filled bubbles appear between fibers
*Induced by diabetes, smoking, drugs, UV, viruses
Macular degeneration - aging - thining of macula
Diabetes - damage to blood vessels of retina
What part of the ear is responsible for hearing and hearing and balance
External - hearing
Middle - (auditory/eustachian tube, ossicles, Malleus, incus, stapes, windows) hearing
Inner (Cochlea (hearing) & semicircular/vesibule (balance)- hearing and balance
Where is endolymph and perilymph?
Endolymph - in membranous labryrinth
Perilymph - space between membrane and periosteum of labyrinth
What is the pathway for hearing?
Vibration to AP
- Vibration enters ear -> vibrates tympanic membrane -> vibrates malleous->Incus-> stapes->Oval window
- Oval window communicates with vestibule -> Scala vestibuli (perilymph) ->membranes (endolymph) -> Scala tampani (perilymph) -> round window
- Vibrate hair cells in organ of corti and create an AP
What is the neuronal pathway for hearing?
Cochlear nerve sends info to Cochlear nucleus -> inferior colliculi
Thalamus -> auditory cortex
What is
Deafness?
Conductive deafness?
Sensorineural deafness?
Deafness - hearing loss
Conductive deafness - Conditions that interfere with vibrations to inner ear (damaged tympanic membrane, otis media, blockage, ostosclerosis)
Sensorineural deafness - death of hair cells or any nervous system elements (factory workers, musicians)
What is static equilibrium?
Dynamic equilibrum?
Static equilibrium - the orientation of head when body is stationary
- *Dynamic equilibrum**
- *Linear acceleration** - when body is moving in a straight line (elevator)
Angular acceleration - rotate - spinning in chair, car turning corner
Utricle has macula that detects ______movment
Saccule has macula that dectect _________movment
What is Macula?
Utricle = horitontal (left to right)
Saccula = veritcle (up and down)
Gelatin mass weigthed by ottoliths which moves in response to gravity. then generates an AP
What is the neuronal pathway for balance?
Vestibular nerve -> Vestibular nucleus send axons to cerebellum & motor nuclei & thalamus -> Cortex
