Exam 4 Flashcards
ANS, Sensory Physiology, Vision, Hearing
Difference between Autonomic Nervous System (ANS) and Somatic Nervous System
ANS- Involuntary control
Somatic Nervous System- Voluntary control
What are general properties of the ANS
Visceral Motor division
Control glands, cardiac and smooth muscles
Regulates unconscious processes to maintain homeostasis
What are the 2 divisions of the ANS
Parasympathetic and Sympathetic
Difference between Sympathetic and Parasympathetic
Sympathetic- Fight or flight response; increase HR, BP, airflow, blood glucose…
Parasympathetic- Rest and digest; calming, digestion and waste elimination, body maintenance
what is Autonomic tone
normal rate of activity for both sympathetic and parasympathetic to maintain homeostasis
Explain what happens during a Visceral Reflex
Receptor detect stimulus, Afferent neuron sends signal to CNS, Efferent neuron sends signal back to effectors in PNS (glands/muscles), ANS MODIFIES effector activity (increase/decrease) in response
What is the White Rami Communcanta
Myelinated communication structure in PREganglionic neurons
what is Gray Rami Communicans
Unmyelinated communication structure in Postganglionic neurons
Preganglionic neuron vs postganglionic neuron
Pre- from CNS out to ganglia, White myelinated rami
Post- from synapse neuron to target organ, Gray unmyelinated rami
What division of the CNS does Sympathetic response
ThoracoLumbar division (T1-L2)
What division of the CNS does Parasympathetic response
CranioSacral Division
What is the sympathetic trunk/ Sympathetic chain ganglia
Place where pre and post ganglionic neurons synapse in ANS
What are the properties of Pre and post ganglionic neurons in Sympathetic division
Pre- short, and run from CNS to ganglion trunk
Post- long, run from ganglion to effector organ
where does synapse between pre and post ganglionic nerves occur in sympathetics
sympathetic trunk
for parasympathetics distinguish characteristics between Pre and Post ganglionic nerves
Pre- long, run from CNS to ganglionic trunk
Post- short, run from ganglionic trunk to effector organs
Why is pre ganglionic neurons short in Sympathetics and long in parasympathetics
Because the Parasympathetics division is the CranioSacral area of the CNS so it has a longer way to travel to reach sympathetic trunk (on both sides of the vertebra) then the Sympathetics do being in the Thoraco Lumbar division of the CNS
Sympathetic Division
Fight/ flight response, expend energy
Preganglionic neuron= short
Thoracolumbar region
Synapse at sympathetic trunk
4 pathways of preganglionic fibers
What is the route UP TO the white rami communicans for sympathetics
Lateral horn of gray matter-> Ventral Horn-> Ventral Root-> Mixed spinal nerve -> ventral Ramus-> White Rami Communicans
What are the pathways of neurons in the sympathetic pathways after synapsing at the sympathetic trunk
- Preganglionic neuron will enter the sympathetic trunk, synapse at same spot and leave as post ganglionic neuron. (enter at T3 leave at T3)
- Enter sympathetic trunk and move 1-2 ganglia higher/lower, synapse and leave at new position. (enter T3 leave T1)
- Doesn’t synapse at sympathetic trunk, continues to Abdominal aorta, synapse with collateral/ prevertebral ganglia. Exits as postganglionic nerve to innervate digestive, urinary and reproductive organs.
- Preganglionic neuron travels through sympathetic trunk and through abdominal aorta to Adrenal Medulla in Adrenal gland and synapses to release Epinephrine and norepinephrine
What is a Splanchnic nerve
Preganglionic neuron that has traveled through the sympathetic trunk and synapses with a collateral/ pre vertebral ganglia
What are the 3 Collateral Ganglia/ Prevertebral ganglia and where are they found
All found in abdominal aorta
Celliac ganglion
Superior Mesenteric ganglion
Inferior Mesenteric Ganglion
What neurotransmitters are released in Sympathetic nervous system
Epinephrine and Norepinephrine
What Neurotransmitter is released in Parasympathetic nervous system
Acetylcholine
What Neurotransmitter is released in Somatic Nervous System
Acetylcholine
Define Cholinergic fibers and in which division of the ANS is it used
Release Acetylcholine (ACH)
ach released for both PREganglionic neurons in parasympathetic and Sympathetic; AND at the POSTganglionic neuron for only Parasympathetics
Define Adrenergic
releases Epinephrine (EPI) and Norepinephrine (NE)
EPI, and NE only released at POSTganglionic synapse in Sympathetic nervous system
Characteristics of Parasympathetics
Rest and Relax
Conserve energy
Cranial nerves (III,VII,IX,X)
DOES NOT INNERVATE SKIN OR BLOOD VESSELS
S2-S4 via pelvic splanchnic nerves
CranioSacral division
Postganglionic fibers=short
What is Cranial Nerve III (3) do
responsible for pupil and pupil diameter
What do cranial nerves VII, IX do
Involved in glands-> dry mouth salivate
What does cranial nerve X do
Vagus nerve
Innervate everything below neck. Heart, lungs, gallbladder, pancreas, large intestines…
Nicotinic receptors
Parasympathetic receptor for Acetylcholine
Somatic (voluntary skeletal).
Excitatory for skeletal muscles (contract)
what is the significance of the adrenal medulla
Located within adrenal gland.
Secrests Norepinephrine and Epinephrine
Enhance fight/flight response
Muscarinic receptors
found in heart
Parasympathetic receptor for ACH
Relaxes heart rate, slow down BP
HR and BP
What is Alpha 1 receptor
Blood vessels in skin and digestive organs
Sympathetic receptors stimulated by NE and Epi.
Stimulatory response =>Constrict smooth muscles and blood vessels
What are alpha 2 receptors
found on blood vessels going to skeletal muscles
Sympathetic receptors stimulated by NE and Epi
Inhibitory response=> dilate blood vessels in skeletal muscle
What are Beta 1 receptors. What compound is a Beta 1 blocker
Found on heart
Sympathetic receptors stimulated by NE and Epi
Stimulatory Response=> Increase HR and BP
Propanolol is Beta 1 blocker=> slow HR and BP
What is a Beta 2 receptor
Found in Bronchioles of lungs
Inhibitory response->Dilate bronchioles for more air intake
Sympathetic receptors innervated by Epi ONLY
what is the sympathetic and parasympathetic response in abdominal cutaneous blood vessels
Sympathetic- decrease Blood flow by constricting vessels via Alpha 1 receptors
Parasympathetic- No response. Parasympathetics don’t innervate skin or blood vessels
What is Vasomotor tone
Blood vessels surrounded by smooth muscles will constrict/dilate based on tissue need (more or less blood)
Function of the Hypothalamus in regards to the nervous system?
Control Autonomic NS (parasympathetics and sympathetics) as well as the Endocrine system
What is the function of the Adrenal Medulla
Within the Sympathetic nervous system, causes the release of Epi and NE. Enhances a response
What is the function of the urinary bladder with the ANS
Sympathetics- causes bladder walls to relax and sphincter contract
Parasympathetics- Causes bladder walls contract and sphincter relax
what drug blocks Muscarinic
Atropine=> Found on receptors in the heart
increases HR and BP
What drug blocks Nicotinic Receptors
Curare
Receptors found on skeletal muscles. Causes Paralysis
Sensation
Sate of external/ internal awareness
Characteristics of sensation
Projection, adaption, afterimages, modality
modality
type of stimulus (pain, temp)
Adaptation
Look at image, look away and still see image
what type of stimulus info can be conveyed
modality, location of stimuli, intensity, duration
Chemoreceptors
Chemical receptors, Taste and smell
Thermoreceptors
temp internal and at skin
Nociceptors
Pain Receptors
Mechanoreceptors
Touch receptors, need to be physically deformed for stimulus
Baroreceptors
Blood pressure receptors in aeorta and coratids
Photoreceptors
Visual receptors
What receptors detect internal stimuli like HR, BP,pH
Enteroreceptors
what receptors are found in muscles, joints, tendons and give the body a sense of position
Proprioreceptors
What receptors sense stimuli external to the body
Externoreceptors
What are the 2 ways receptors are distributed
General sense- Widely distributed, associated with skin; pain, temp, touch
Special senses- Vision, taste, Hearing
Do large receptor fields have low sensitivity or high sensitivity
Low Sensitivity (on back)
DO small receptor fields have low sensitivity or high sensitivity
High sensitivity (fingers, and toes)
What is the 2 point discrimination test
2 prongs close together, slowly moved apart until you can feel both prongs. Used to determine where 2 receptors are
What Is lateral inhibition
Inhibit receptor next to chosen receptor
What are Meissner’s corpuscles
receptors sensitive to light touch, and low frequency vibration
What sensations do the hair root plexus respond to
Sensitive to light touch
Free nerve endings
Respond to pain, TEMP, itch, joint movement
Pacinian corpuscles
Receptors deep in dermis. Detect deep pressure, vibrations and proprioreception
What is referred pain
Perceived pain location isn’t where pain is actually coming from
What are the special senses
Taste,smell,hearing,touch,vision,equilibrium
What are proprioreceptors
Sense the body in space
Tendon organs (Golgi tendon organs)
Location in junction where muscles and tendons join. Monitor contractions; inhibit motor neurons to decrease contractions
Olfaction
smell receptors,
Nasal mucosa, olfactory nerve, olfactory bulb, Olfactory tract, temporal lobe
Olfactory senses DONT travel to thalamus
LIMBIC SYSTEM= emotional response to odors
Gustation
Taste receptors
5 taste sensations: Sweet, Bitter, Salty, Sour, Umami
Which sensory nerve are used for taste
CN VII (Facial) anterior 2/3 of tongue
CN IX (glyssopharangeal) posterior 1/3 tongue
CN X (Vagus) back of mouth
What is the pathways for gustation
1 of 3 Sensory nerves, brain stem, thalamus, parietal lobe
What is vision
Perception of light reflected from objects un the environment
function of choroid
Absorb excess light
function of silary body
Smooth muscle changes shape of lens
Function of lens
Focus image onto retina
function of iris
Maintain shape of pupil
what is the Tunica Fibrosa
Outer layer (Outer tunic) of the eye. Made of the sclera and the cornea
What is the Tunica Vasculosa
Middle layer (middle tunic) of the eye. Made of Choroid, Cilary body, Iris, and pupil
What is the Tunica Interna/ Nervous tunic
Inner layer (inner tunic) of the eye. Made of retina and optic nerve
Function of fovea centralis
Focal point of the eye. Highest density of cones.
Function of Optic Disc
Where optic nerve exits eye. Also know as blind spot bc no receptors found here
what are the 2 types of photoreceptors
Rods and Cones
What is the function of Rods
Black and white vision
Used in low light
Low visual acuity (not very clear image)
What is the function of cones
Used in bright light
Clear images
most found around fovea centralis
Red, blue, green cones
What is the Macula of the eye
Area where the focal point is located
what is Aqueous Humor
a water based solution in the ANTERIOR CAVITY of the eye.
Maintain intraoccular pressure and holds retina in place.
What is Vitreous Humor
water based liquid Located in the Posterior cavity of the eye and is used to maintain intraoccular pressure
what is the tarsal plate
Firmness of superior and inferior eyelid
Medical term for eyelid
Palpebre
what is the function of the tarsal Meibomian
Secrete fluid at ends of the tarsal plate (top and bottom of eyelid) to prevent the eye from sticking
Where is the Lateral and medial canthus (commissure) located
media and lateral corners of the eye
What is the Caruncle of the eye
fleshy area at medial commissure, where eye boogers form
What are Sebaceous ciliary glands
Glands around eyelashes that secrete oil ad promote eyelash health and prevent eyelashes from sticking
What is the conjunctiva of the eyeball
Inner eyelid, helps keep eye moist. 2 parts Palpebra conjunctiva and Bulbar conjunctiva
What is the Lacrimal pathway
Lacrimal gland, lacrimal ducts, lacrimal punctum, lacrimal canal, lacrimal sac, nasolacrimal duct, nasal cavity
What is the function of the lacrimal apparatus
Crying, moisture, immune fighting
Function of lacrimal glands
found superior lateral to eyebrow, produce tears that sweep across eye to lacrimal punctum
Emmetropia
normal vision
Refraction
Bending of light
occur when light passes through at any angle other than 90*
Takes place at cornea
performed by lens
What kind of lens to human have on their eyes
Biconvex lens
Myopic eye
Nearsighted
Hyperopic eye
farsighted
Emmetropic
normal visin
What happens to the lens for distant vision
Lens will flatten
What happens to the lens for close vision
Lens will bulge
what accommodation can occur in vision to make vision more clear
Pupils constrict- limiting light
Eyeball converge- cross-eye
what part of the brain control voluntary eye movement (fixation)
Frontal lobe ( premotor area)
What part of the brain controls involuntary fixation (movement)
Superior collulicus of midbrain. (reflex part)
What is Binocular vision
What humans have. Give greatest depth perception
What is Diplopia
Double vision
What Is Strabismus
Lazy eye
Rhodopsin
Visual pigment of rod cells
2 major parts: Protein Opsin and Retinal
What are Bipolar cells
1st order neurons
Communicate with Photoreceptors (rods and cons)
Synapse with ganglion cells
What are Ganglion Cells
2nd order neurons
their axons form the optic nerve
what are Horizontal and Amacrine cells
Supportive cells to bipolar and ganglion cells
Describe visual acuity test
Snellen eye chart (close 1 eye, what letter do you see)
20/20= normal
10/20= nearsighted
25/20= Farsighted
Describe the Pupillary reflex
Flashlight in eye causes PNS to constrict pupils
what is direct / Ipsilateral pupillary reflex
pupil same side as flashlight will constrict
What is indirect/ Contralateral pupillary reflex
Both pupils constrict when flashlight in 1 eye
What is the visual Pathway
Optic nerve, optic chiasma, optic tract, thalamus, occipital lobe
Medical name for outer ear
“Auricle” / “Pinna”
Where are ceruminous glands found and what do they do
Found in the auditory canal and secrete Cerumin (ear wax)
name the 3 auditory Ossicles and what is their purpose
Transmit sound from outer ear to inner ear
Malleus-“Hammer”
Incus- “Anvil”
Stapes- “stirrup”
what are the parts of the middle ear
3 Ossicles
Oval Window
Round window
Auditory tube
Tympanic membrane
In which part of the ear is the auditory canal located
Outer ear
what is the function of the auditory tube
Opens from middle ear down to throat.
Equalizes air pressure on both sides of eardrum
Opens during swallowing or yawning
What are the main parts of the inner ear
Cochlea
Simu-circular canals
Osseous Labyrinth
Membranous labrynth
Cochlea
Found in inner ear , responsible for hearing
Semi-circular canals
Found in inner ear. Responsible for equilibrium
Osseous labyrinth
“bony labyrinth
Surrounds the Cochlea and semi-circular canals, filled with Perilymph
Membranous labrynth (cochlear duct)
membrane within osseous labyrinth filled with endolymph. Helps transmit sound waves
Vestibular membrane
Top part of membranous labyrinth, continues until apex of cochlea when its then considered basilar membrane
Basilar membrane
part of the membranous labyrinth starting at the apex of the cochlea
Spiral Organ (Organ of Corti)
hearing organ found inside cochlea that Contains hair receptors responsible for hearing found on top of the basilar membrane.
how are vibrations perceived as noise
Vibrations make their way to the endolymph inside the cochlea and vibrate the hairs of the organ of corti which we perceive as noise
Frequency
How often something is happening
Amplitude
Loudness of sound.
Tall amp.= loud sound
small amp.= softer sound
where is high vs low frequency perceived in the cochlea
high Frequency= base of cochlea
Low frequency= Apex of cochlea
What is the Tympanic reflex
a way of protecting the cochlea in response to loud and prolonged noise.
Designed for slowly building noise
Damage is irreversible
Explain how tympanic reflex works
Tensor Tympani (muscle connected to Malleus) pulls eardrum to reduce mobility of stapes thus reducing noise
what is the auditory pathway from sound to brain
sound-> Auricle(outer ear)->tympanic membrane->malleus->Incus->Stapes-> Oval Window-> Cochlea-> Perilymph-> cochlear duct(membranous labyrinth)-> endolymph-> organ of corti-> cranial nerve VIII (8)-> vestibularcochlear nerve-> Thalamus-> Temporal lobe
What controls equilibrium in our body
Vestibular Apparatus
Explain Vestibular apparatus
Broken down into 2 parts: Vestibule and Semi-circular canals.
Work together to maintain balance and equilibrium in body
Vestibule
Equilibrium in LINEAR movement (vertical and horizontal)
Pathways connecting to semi-circular canals
2 parts: Utricle: horizontal movements. Saccule: vertical movements
Otolithic membrane
What is the Macula
Houses receptors within Vestibule that help with equilibrium
What is the Otolithic Membrane
Jello like membrane within Vestibule that contains Otolith (ear crystals) that determine head position and equilibrium
Semi-circular canals
Help to maintain equilibrium
monitor movement in x,y,z plane (rotational movement)
2 parts: Crista Ampullaris
Cupula
Crista Ampullaris
Hair cells
in semi-circular canals
Cupula
Whole structure of Crista ampullaris, nerve connect to hair, and otolithic membrane all together.
Move with inertia or momentum (spinning).
Activated by endolymph moving in opposite direction as capula
when spinning; after stopping, capula keeps being pushed which causes dizziness
Dynamic whole body equilibrium
Balance and equilibrium involves input from all kinds go senses that work together to keep body upright, straight and not dizzy