Physiology Exam 2

Front 1

PNS: General Org of ANS Pathway

Back 1

2 consequtive motor neurons
applies to both symp/parasympathetic NS's
(picture)

Front 2

PNS: ANS

Back 2

-part of PNS not under voluntary control
-Divisions: sympathetic & parasympathetic NS

Front 3

sympathetic NS:

Back 3

associated anatomically w/ thoracic & lumbar regions of spinal cord; thoraco-lumbar

Front 4

parasympathetic NS:

Back 4

associated anatomically w/ cranial & sacral regions of brain & nerves ofspinal cord (cranio-sacral)

Front 5

Structure of Sympathetic NS

Back 5

sympathetic chain ganglia: -found from cervical to lumbar region on both sides of sp cord
-ganglia on one side interconnected
-ganglia connected to spinal nerves on spinal cord
-1st visceral efferent neuron's cell body found in lateral horn of gray matter

Front 6

axon of neuron comes out of spinal cord to symp ganglion & can do 1 of 3 things:

Back 6

1. axon synapses w/ 2nd visceral efferent neuron in ganglion @ entry level
2.axon enters symp chain, goes up chain, & synapses w/ 2nd visceral efferent neuron @ this higher level
3.axon enters symp chain, goes down chain, & synapses w/ 2nd visceral efferent neuron @ this lower level

Front 7

in all 3 cases, after synapse:

Back 7

2nd visceral efferent neuron sends its axon through the autonomic nerve to an effector

Front 8

ANS: generalizations

Back 8

-1st visceral efferent axon is relatively short in length & carries AP to symp ganglion
-2nd visceral efferent axon is relatively long in length & carries AP to visceral effector

Front 9

Structure of Parasympathetic Pathway:

Back 9

1.cranial region
2.sacral region

Front 10

cranial region:

Back 10

1.1st visc eff axon passes over some CRANIAL nerve (III,VII,IX,X) & extends to a parasymp ganglion near a visceral effector (very close to organ receiving stim)
2.1st visc axon synapses w/ 2nd visc eff neuron in parasymp ganglion
3.2nd visc eff axon innervates a visceral effector

Front 11

sacral region:

Back 11

1.1st visc eff axon emerges from L region sp cord & passes over PELVIC nerve to parasymp ganglion near visc effector
2.1st visc axon synapses w/ 2nd visc eff neuron in a parasymp ganglion
3.2nd visc eff axon extends to & innervates visc effector

Front 12

parasymp pathway generalizations:

Back 12

1st visc axon is long in length & 2nd vis eff axon is short in length

Front 13

General Autonomic Principles

Back 13

1.autonomic reflexes tend to restore homeostasis very quickly
2.dual autonomic innervation
3.single autonomic innervation
4.autonomic NT, specific & nonspecific to system
5.autonomic antagonism & dominance

Front 14

dual autonomic innervation:

Back 14

effector receives both parasymp & symp innervation

Front 15

single autonomic innervation

Back 15

effector receives either/or parasymp/symp innervation

Front 16

autonomic NT

Back 16

1.acetylcholine (Ach)
2.norepinephrine (NE)

Front 17

Acetylcholine

Back 17

cholinergic neuron if release Ach
-includes:
1.all preganglionic neurons (both para/symp)
2.all parasymp postganglionic neurons
3.some symp postganglionic neurons
(entire parasymp NS releases Ach)

Front 18

Norepinephrine

Back 18

adrenergic neuron if release NE
-includes: most symp postganglionic neurons

Front 19

autonomic antagonism & dominance:

Back 19

applies to dual innervation
-NT of highest concentration produces effect (picture)

Front 20

NS: Senses

Back 20

1.Sensory unit
2.Receptors

Front 21

Senses: Sensory Unit

Back 21

3 elements:
1.receptor
2.neural pathway
3.interpretation center

Front 22

receptor:

Back 22

-detects stimulation & changes to NS language
-special cell or part of sensory neuron

Front 23

neural pathway:

Back 23

path AP takes from receptor to brain

Front 24

interpretation center:

Back 24

-in cerebral cortex
-interprets sensation/final analysis of out/input

Front 25

Senses: Receptors

Back 25

detect stimuli from internal or external environment
1.Specificity
2.Function
3.Types

Front 26

Receptors: Specificity

Back 26

specific to 1 kind of stimulus
-variation related to excessive stimulation that changes sensation to pain:
1.mechanoreceptors: respond to excess stretch
2.temp receptors: hot=burning sensation -> excess heat=pain

Front 27

Receptors: Fxn

Back 27

respond to specific stimulus -> produce generator potentials (local depolarizations) -> summate & produce AP

Front 28

Receptors: Types

Back 28

1.Exteroreceptors
2.Proprioceptors
3.Interoreceptors

Front 29

Exteroreceptors:

Back 29

-receive stimuli from outside body
-pick up sensations from skin, eye, ear, nasal cavity & tongue

Front 30

Exteroreceptors: Cutaneous/Skin receptors

Back 30

located in dermis/tongue
-respond to light touch
-detect deep pressure
-detect temperature
-detect pain

Front 31

Cutaneous/Skin receptors: light touch

Back 31

ruffinis corpuscles, meiseners corpuscles, Krause's end bulbs, Merkels Discs

Front 32

Cutaneous/Skin receptors: deep pressure

Back 32

pacinian corpuscles in subcutaneous tissue & CT around joints

Front 33

Cutaneous/Skin receptors: temperature

Back 33

free nerve endings
-both heat (skin temp increase 30-45 degC; 45deg kills tissue & sense pain)
& cold (skin temp decrease 40-10 degC

Front 34

Cutaneous/Skin receptors: pain

Back 34

free nerve endings throughout entire body generally, except in the brain

Front 35

Exteroreceptors: Types of pain

Back 35

1.somatic pain
2.visceral pain
3.referred pain

Front 36

somatic pain:

Back 36

1.superficial: comes from skin only
2.deep: arises from skeletal musc & tendons

Front 37

visceral pain:

Back 37

from internal organs

Front 38

referred pain:

Back 38

pain originates in muscle tendon or body organ; pain perceived as coming from superficial area of skin
1.deep somatic
2.visceral
3.never superficial somatic

Front 39

referred pain ex:

Back 39

angina & appendicitis
-theory:
1.brain: where sensations interpreted
2.interneuron @ sp cord: sends AP to brain
3.sensory neuron: sends AP to interneuron
-brain familiar w/ pain originating from Larm & unfamiliar w/ pain from heart, so interprets pain coming from Larm b/c it can't seperate them (pic)

Front 40

Proprioceptors:

Back 40

muscles, joints & tendons, muscle spindles, golgi tendon organs

Front 41

Interoreceptors:

Back 41

deep body organs
1.stretch receptors
2.baroreceptors
3.chemoreceptors
4.temperature receptors

Front 42

Interoreceptors: stretch receptors

Back 42

respond when organ stretches
-lungs

Front 43

Interoreceptors: baroreceptors

Back 43

respond to change in pressure
-bv's & heart
-RA, aorta, sup/inf vena cavae, carotid sinus

Front 44

Interoreceptors: chemoreceptors

Back 44

respond to change in chemical composition of ECF
-aorta, carotid artery, medulla oblongata

Front 45

Interoreceptors: temperature receptors

Back 45

monitor temperature of blood
-hypothalamus

Front 46

Special Senses:

Back 46

1.Gustatory Sense (taste)
2.Olfaction (smell)
3.Vision
4.Auditory & Equilibrium Senses

Front 47

Gustatory Sense (Taste)

Back 47

1.Taste Cells
2.innervation
3.interpretation center

Front 48

Gustatory Sense: Taste cells

Back 48

-located in taste buds, found in taste papillae on tongue
-5 kinds: sweet,sour,bitter,salty, umami (meat protein)
-universely distributed, not localized

Front 49

Gustatory Sense: taste route

Back 49

sensation->saliva->surface tongue->b/w papillae->stimulate/enter specific taste bud

Front 50

Gustatory Sense: Innervation

Back 50

-facial nerve supplies taste buds on anterior 2/3 tongue
-glossopharyngeal nerve supplies taste buds on posterior 1/3 tongue

Front 51

Gustatory Sense: interpretation center

Back 51

found in frontal lobe of cerebrum

Front 52

Olfaction (smell)

Back 52

1.receptors& pathway
2.interpretation center

Front 53

Olfaction: receptors

Back 53

olfactory cells found in high epithelium of nasal cavity
-respond to water or lipid soluble substances & volatilize

Front 54

olfaction route:

Back 54

olfactory cells send AP -> olfactory bulb->olfactory tract/nerve->frontal lobe

Front 55

Olfaction: interpretation center

Back 55

found @ frontal lobe of cerebrum

Front 56

Vision

Back 56

1.structure of the eye
2.physiology of vision

Front 57

Vision: Structure of the Eye:

Back 57

1.layers of tissues
2.cavities & humors
3.Eyelids
4.Lacrimal Apparatus

Front 58

Layers of Tissues:

Back 58

1.sclera
2.cornea
3.choroid coat
4.retina

Front 59

sclera:

Back 59

outer layer; white of the eye; WFCT/collagenousCT;providing for skeletal element

Front 60

cornea:

Back 60

front of sclera; clear tissue; covers iris

Front 61

choroid coat:

Back 61

middle layer; highly vascularized=good blood supply; dark pigmented;
1.posterior choroid
2.anterior choroid

Front 62

posterior choroid:

Back 62

supports retina & provides nutrition to retina

Front 63

anterior choroid:

Back 63

specialized into 2 structures:
1.ciliary body
2.iris

Front 64

anterior choroid: ciliary body

Back 64

-internally: ciliary muscles, smooth musc, involuntary
-in front of ciliary musc: ciliary processes- extensions off main ciliary body; attached to zonular fibers around lens ...

Front 65

all together, ciliary muscles + ciliary processes =

Back 65

suspensory ligament, which attaches ciliary body to lens

Front 66

anterior choroid: iris

Back 66

color part of choroid; opening @ center = pupil; fxn: control amount of light that enters eye by changing the diameter of pupil w/ 2 structures:
1.dilator pupillae
2.sphincter pupillae

Front 67

dilator pupillae:

Back 67

intrinsic muscles that increase pupil opening

Front 68

sphincter pupillae:

Back 68

intrinsic muscles that decrease pupil opening

Front 69

both dilator/sphincter pupillae:

Back 69

smooth muscle, involuntary

Front 70

Retina:

Back 70

inner most layer; sensative to light; lies adjacent to vitreous humor; 6 layers

Front 71

6 layers of Retina:

Back 71

1.photoreceptor neurons
2.bipolar neurons
3.ganglion neurons
4.macula lutea
5. fovea centralis
6.optic disc

Front 72

Retina: photoreceptor neurons

Back 72

-rods or cones
-directly a/g choroid coat
-last row of cells affected by light

Front 73

photoreceptor neurons respond to light rays:

Back 73

initiate AP->rods/cones connect to bipolar layer

Front 74

Retina: bipolar neurons

Back 74

take AP from rods/cones to ganglion neuron

Front 75

Retina: ganglion neuron

Back 75

-next to vitreous humor
-inner-most neurons of retina
-very long axons; converge to one point: optic disc, forming optic nerve

Front 76

Retina: macula lutea

Back 76

"yellow spot"
-posterior center of retina directly behind pupil
-depression @ center: fovea centralis

Front 77

Retina: fovea centralis

Back 77

contains about 3million cones in fovea & about 100million rods outside fovea

Front 78

Retina: optic disc

Back 78

"blind spot"
-convergence of ganglion neurons
-beginning of optic nerve
-@ this point of retina, cant see an image b/c no rods/cones present @ disc

Front 79

Structure of the Eye: Cavities & Humors

Back 79

1.posterior cavity
2.anterior cavity
3.formation & circulation of aqueous humor
4.glaucoma

Front 80

Posterior Cavity:

Back 80

-borders: lens to retina
-contains gel: vitreous humor

Front 81

vitreous humor:

Back 81

helps to maintain intraocular pressure in the eye/keep eye from collapsing

Front 82

Anterior Cavity:

Back 82

-borders: lens to cornea
-made of 2 chambers:
1.anterior chamber: cornea to iris
2.posterior chamber: iris to lens

Front 83

Formation & Circulation of Aqueous Humor:

Back 83

1.blood plama filtered thru capillaries in ciliary processes to
2.post chamb of ant cavity, causes pressure & flows
3.thru pupil
4.into ant chamb of ant cavity; now must be drained out of eye thru
5.canal of schlemm, into
6.small veins in sclera

Front 84

*as aqueous humor moves through the eyes,

Back 84

it leaves nutrients for cornea/lens & carries wastes to veins for disposal

Front 85

problem if flow interrupted:

Back 85

Glaucoma

Front 86

Glaucoma:

Back 86

-pressure >25mmHg (norm=20-25mmMercury)
-lack of drainage: block @ canal of schlemm OR
-too much production: accumulates aqueous humor @ ant cavity
-->pressure expressed backward on retina & damages rods/cones & person has potential to become blind

Front 87

Eyelids:

Back 87

palpebrae
-folds of skin (upper/lower eyelid)
-affected by 2 skeletal muscles:
1.palpebrae superioris: raises upper eyelid
2.orbicularis oculi:closes both eyelids, invol

Front 88

Eyelid: 3 elements

Back 88

1.Palpebral Fissure
2.Conjunctiva
3.Canthus

Front 89

Palpebral Fissure:

Back 89

space b/w upper and lower eyelids

Front 90

Conjunctiva:

Back 90

mucous memb
1.palpebral conj: covers inner surface of both eyelids
2.ocular conj:covers anterior sclera, but not cornea; continuous w/ 1.

Front 91

Canthus:

Back 91

fusion of eyelids
1.lateral canthus: fusion on side of eye
2.medial canthus: next to nose

Front 92

caruncle:

Back 92

little red bump @ medial canthus; land mark for eye doctors

Front 93

Lacrimal Apparatus:

Back 93

1.Lacrimal Glands
2.Lacrimal canals
3.Nasolacrimal Duct
4.Tears

Front 94

Lacrimal Apparatus: Lacrimal Glands

Back 94

-found @ sup-lat region of orbit
-produce/release tears
-tears flow over eye surface->medial canthus, where you find 2 lac canals

Front 95

Lacrimal Apparatus: Lacrimal Canals

Back 95

-1 above & 1 below caruncle
-drains tears off surface of eye
-fxn: keeps conjunctiva moist
-sends tears to lacrimal sac

Front 96

Lacrimal Apparatus: Nasolacrimal Duct

Back 96

-receives tears from lacrimal sac
-sends tears to nasal cavity
-sends small amount, but constant flow

Front 97

Lacrimal Apparatus: Tears

Back 97

1.derive from blood plasma, so nearly same chem comp w/ far less pr
2.keep conjunctiva moist/lubricated so eyeballs can close over them cleanly
3.contains lysozyme that destroys any bacteria coming into eye
4.if dont kill bac, eye infxn: conjunctivitis/"pink eye": inflammation of sclera

Front 98

Vision: physiology of vision

Back 98

1.requirements
2.image focusing
3.stimulation of retina
4.cone stimulation

Front 99

requirements:

Back 99

1.image focus
2.rods & cones rxn
3.transmission of APs
4.visual interpretation center

Front 100

rods&cones rxn-

Back 100

react to light->photochemical rxns; initite APs

Front 101

transmission of APs-

Back 101

thru optic nerve->thru pathways to final destination->cerebral cortex in occipital lobe

Front 102

visual interpretation center-

Back 102

in occipital lobes; final interpretation occurs here

Front 103

image focusing:

Back 103

lens;
1.far vision
2.near vision
3.abberations

Front 104

far vision:

Back 104

emmetropia;
-image >20ft away from eye
-light rays coming to eye @ parallel orientation
-choroid coat in norm anatomical position (tension exerted on suspensory ligament)
-tension makes lens somewhat flattened->low curvature
-image focused on the retina

Front 105

near vision:

Back 105

accomodation;
-object <20ft away from eye
-light rays come in eye divergent from point where image located
-ciliary muscles contract & ciliary body moved forward
-tension reduced on susp lig
-lens has elastic prop, so w/ less tension, becomes > convex->higher curvature
-image focused on retina

Front 106

abberations:

Back 106

1.emmetropia: normal eye
2.accomodation: some abnormality assoc w/ eye
a)myopia
b)hyperopia
c)astigmatism
d)cataracts
3.presbyopia

Front 107

myopia-

Back 107

nearsightedness; can see near
->common cause:ant/post dimensions of eye too long
-refractive power of cornea/lens too strong (focus light rays short of retina in vitreous humor & image blurred)

Front 108

hyperopia-

Back 108

farsightedness; can see far
->common cause:ant/post dimensions of eye too short
-refractive power of cornea/lens too weak (focus light rays behind retina & image blurred)

Front 109

Astigmatism-

Back 109

curvature of cornea/lens is imperfect & person sees parts of image in focus & parts blurred

Front 110

Cataracts-

Back 110

affect the lens;
-lens made up of protein: crystaline
-as age, protein denatured & lens that is usually clear is now opaque ->defracts light rays (rather than refracting them)

Front 111

Presbyopia:

Back 111

near point of eye moves farther away from eye surface w/ age
-greatest change occurring 45-50yo
-lens becomes less elastic w/ age & can no longer accomodate to near objects as did previously

Front 112

Stimulation of Retina:

Back 112

Rhodopsin Cycle;
1.rods contain rhodopsin or 11-cis-rhodopsin
2.light ray shines on
3.11-cis-retinal changes to trans-retinal + opsin
4.trans-retinal seperates from opsin
5.w.o light, trans-retinal changes back to 11-cis-retinal & but back together w/ opsin thru chemical rxn

Front 113

11-cis-rhodopsin

Back 113

composed of opsin (protein) & 11-cis-retinal (derived from vit A)

Front 114

all in all,

Back 114

-light breaks down rhodopsin
-dark areas put rhodopsin back together

Front 115

APs started:

Back 115

in rods when broken down into trans-retinal

Front 116

Cone Stimulation:

Back 116

3 types of cones & primary colors:
1.Erythrolabe: red cone
2.Cyanolabe: blue cone
3.Chlorolabe: green cone

Front 117

cyan-

Back 117

-blue light stimulates cyanolabes->stimulates APs
-green light stimulates chlorolabes->stimulates APs
-both sent to occipital lobes

Front 118

most common colorblindness:

Back 118

red/green (minor blue/yellow)

Front 119

Auditory & Equilibrium Senses:

Back 119

auditory vestibular apparatus:
1.external ear
2.middle ear
3.inner ear

Front 120

external ear:

Back 120

1.pinna/auricle
2.ear lobe
3.external auditory meatus
*tympanic membrane=border b/w outer/middle ear

Front 121

pinna-

Back 121

-elastic cartilage +skin
-directs sound waves to external auditory canal

Front 122

ear lobe-

Back 122

-adipose tissue, CT, skin
-purely cosmetic; no hearin fxn

Front 123

external auditory meatus-

Back 123

-tube extends from pinna->middle ear
-opening covered by eardrum/tympanic membrane

Front 124

middle ear:

Back 124

hollow space in temporal bone;
1.ear ossicles
2.openings

Front 125

ear ossicles-

Back 125

3; smallest bones in head;
-fxnal bones that articulate w/ each other:
1.malleus-articulates w/ tympanium
2.incus
3.stapes-articulates w/ membrane oval window

Front 126

Openings:

Back 126

1.external auditory meatus
2.oval & round windows
3.mastoid sinuses (cells)
4.eustachian tube

Front 127

oval & round windows-

Back 127

covered by membranes

Front 128

mastoid sinuses-

Back 128

spaces in mastoid process

Front 129

eustachian tube-

Back 129

auditory tube; connects middle ear to mouth

Front 130

Inner ear:

Back 130

housed in petrous process in temporal bone;
-bony & membranous labyrinths

Front 131

bony -> membranous labyrinths

Back 131

1.semicircular canals 3 ->semicircular ducts
2.vestibule->utricle & saccule
3.cochlea->cochlear duct/scala media

Front 132

Inner Ear fluids:

Back 132

1.perilymph: fluid b/w bony & memnranous structures
2.endolymph: found inside membranous structures
-they dont mix

Front 133

membranous labyrinth-

Back 133

1.semicircular canals
2.ampulla
3.utricle
4.saccule
5.cochlear duct

Front 134

membranous labyrinth: semicircular ducts

Back 134

-all arranged 90deg to one another
-named for direction they point: superior/lateral/posterior
-connect to ampullae found @ base of ducts ... only 5 b/c superior/posterior share

Front 135

membranous labyrinth: ampulla

Back 135

1.crista ampullaris
2.cupula
3.fxn

Front 136

ampulla-crista ampullaris

Back 136

cluster of neurons w/ hairlike ext off surface making contact w/ cupula

Front 137

ampulla-cupula

Back 137

gelatin like/strong gel tht contacts hairlike endings starting APs
-movement of endolymph causes cupula to move AP

Front 138

function of semicircular ducts & ampulla

Back 138

provide us w/ a sense of angular acceleration or rotation

Front 139

rotation pattern:

Back 139

head rotates->endolymph moves->cupula moves->stimulates crista neurons->send AP over vestibular branch XIIIcranial nerve-> to brain & body receives angular sense
*impt in balance & posture

Front 140

membranous labyrinth: utricle

Back 140

-located in sup region of vestibule
-connected to saccule in vestibule
-all 5 ampullae connect to utricle
1.macula
2.otolithic membrane
3.granules
4.fxn

Front 141

utricle-macula:

Back 141

cluster of sensory neurons w/ hairlike ext off surface

Front 142

utricle-otolithic membrane

Back 142

above macula; gel like; in contact w/ hairlike ext's

Front 143

utricle-granules

Back 143

made of calcium carbonate called otoconia, statconia, otoliths
-lie on top of otolithic mem & weight it down/keep in place

Front 144

utricle: fxn

Back 144

1.proprioceptor for the head (tells what position head in)
2.gives us a sense of linear acceleration in the horizontal plane
3.endolymph in utricle->head moves endolymph->stimualtes macula->sense of location

Front 145

membranous labyrinth: saccule

Back 145

-similar to utricle
-connected to ut. by ductus reuniens connecting to cochlear duct
-fxn:provide for vertical plane linear acceleration
*also passes over vestibular branch XIIIcranial nerve->brain

Front 146

membranous labyrinth: cochlear duct

Back 146

scala media;
1.triangular in xsection
2.extends to cochlea in form of spiral
3.forms compartments inside cochlea
4.cochlear duct is shorter than cochlea, so connection @ tip b/w scala vestibuli & tympani: heligotrema
5.organ of corti

Front 147

compartments inside cochlea:

Back 147

1.scala vestibuli: perilymph
2.cochlear duct: endolymph
3.scala tympani: perilymph

Front 148

organ of corti:

Back 148

-inside cochlear duct
-rests on basilar memb b/w scala media & tympani
-cluster of sensory neurons w/ hairlike ext in contact w/ tectorial membrane

Front 149

organ of corti fxn:

Back 149

-detect sound waves in the inner ear
-place theory of sound detection

Front 150

place theory of sound detection:

Back 150

sound waves cause vib in perilymph of s.vestibuli->transferred to vestibular memb->to endolymph of s.media->vib's now occur in basilar memb->causes organ of corti to vib & hairlike ext contact tectorial memb stimulating organ of corti neurons...

Front 151

organ of corti neurons next to oval window:

Back 151

detect high pitch sounds

Front 152

organ of corti neurons next to helicotrema:

Back 152

detech low pitch sounds

Front 153

neurons send AP->

Back 153

over auditory branch of XIIIcranial nerve to brain, where sound waves interpreted

Front 154

tranmission & detection of sound in ear:

Back 154

sound waves directed to ext aud meatus by pinna->cause mvmt in tympanium->transferred to malleus, incus, stapes, round window memb->transferred to perilymph in s.vestibuli->transfers to endolymp s.media

Front 155

from s.media

Back 155

transferrred to basilar memb w/ organ of corti->causes stimulation in organ corti->stimluates APs to XIIIcranial nerve->brain & interpretted

Front 156

mvmt of basilar memb or perilymph in s.tympani:

Back 156

in contact w/ round window mem->middle ear & at this point sound waves are eliminated (would hear echos if didnt stop)

Front 157

Circulatory System: Components

Back 157

1.fluids: blood, lymph
2.vessels: pathways for flow of fluids; BV, lymphV
3.heart: muscular pump

Front 158

Circulatory System: Subdivisions

Back 158

1.Cardiovascular system: heart, BVs, blood
2.Lymphvascular system: lymph nodes, lymphVs, lymph

Front 159

Cardiovascular System:

Back 159

1.heart
2.heart structure

Front 160

heart: location

Back 160

mediastinum: space b/w lungs, sternum, vertebral column

Front 161

heart: base

Back 161

top of atria

Front 162

heart: apex

Back 162

inferior end, tip of left ventricle only
-tip of LV is found in the 5th intercostal space (b/w 5/6ribs) 2/3 left of midline

Front 163

heart structure:

Back 163

1.wall
2.pericardial sac
3.chambers
4.cardiac cycle

Front 164

heart structure: wall

Back 164

-3 layers of tissue
1.endocardium:endothelium, single layer from inner layer bv's
2.myocardium: cardiac muscle; greatest bulk of heart
3.epicardium: visceral pericardium; serous memb

Front 165

heart structure: pericardial sac

Back 165

-surrounds heart
-pericardial space/cavity just under sac containing pericardial fluid

Front 166

pericardial sac comp:

Back 166

1.outer layer:connective tissue memb
2.inner layer: serous memb contacts pericardial cavity
3.pericardial cav contains pericardial fluid
4.function of fluid is to reduce friction b/w heart & other structures

Front 167

heart structure: chambers

Back 167

1.upper chambers
2.lower chambers

Front 168

upper chambers

Back 168

-L&R atria
-thin walled w/ small amt pumping

Front 169

R atrium

Back 169

-connected to superior and inferior vena cavae
-Ratrio-ventricular orifice connects RA to RV
-tricuspid valve in orifice

Front 170

L atrium

Back 170

-connects to 4 pulmonary veins at base of L atrio-ventricular orifice opening into L ventricle
-bicuspid/mitral valve

Front 171

lower chambers

Back 171

-L&R ventricles
-thick walled & do most of pumping action
-interventricular septum b/w

Front 172

R ventricle

Back 172

-connects to pulmonary trunk sending blood to lungs

Front 173

L ventricle

Back 173

-connected to aorta or aortic arch sending blood to every part of body except lungs

Front 174

papillary muscle

Back 174

ext of ventricular wall; connected to chordae tendinae, which are connected to tricuspid/bicuspid valve

Front 175

heart structure: cardiac cycle

Back 175

mechanical action of heart during a single heart beat
1.diastasis & diastole
2.atrial systole
3.atrial diastole
4.ventricular systole
5.ventricular diastole

Front 176

systole vs diastole:

Back 176

1.systole:contraction of vent
2.diastole:relaxation of vent

Front 177

diastisis:

Back 177

heart is at complete relaxation b/w cycles

Front 178

diastole:

Back 178

ventricles relaxing

Front 179

atrial systole:

Back 179

-both atria contract at same time together
-prior to this blood filled heart to 70% of its capacity
-remaining 30% to be reached by atria systole

Front 180

atrial diastole:

Back 180

atria relaxing

Front 181

ventricular systole:

Back 181

-ventricles contract, blood flows from LV to aorta and from RV to pulmonary trunk
-papillary muscles contract to ensure bicuspid,tri valves stay closed

Front 182

ventricular diastole:

Back 182

vent's relax->reduces pressure in vent's->creates tendency for blood to flow back into vent's, but prevented when semilunar valves (in aorta&pulmonary trunk) close to prevent backflow

Front 183

heart structure: heart sounds

Back 183

-sounds made during cardiac cycle
1.normal
2.abnormal

Front 184

heart sounds: normal

Back 184

1.sysotlic
2.diastolic

Front 185

systolic sound:

Back 185

1st; long duration; low pitch; caused by contraction of ventricles->atrioventricular valves closing

Front 186

diastolic sound

Back 186

2nd; short duration; high pitch; louder; caused by relaxation of ventricles->semilunar valves closing

Front 187

abnormal heart sounds:

Back 187

murmurs; due to malfxning heart valves; hear extra sound
1.stenosis
2.valvular insufficiency

Front 188

stenosis:

Back 188

portions of valves fuse&dont open to their full extent; blood coming thru smaller opening @ faster rate ->causes abnormal sound

Front 189

stenosis occurs:

Back 189

largely in bicuspid/aortic semilunar valve & somewhat in tricuspid/pulmonary trunk semilunar valves
"Bicuspid stenosis" "aortic stenosis"

Front 190

valvular insufficiency:

Back 190

incompetence; portion of heart valve lost due to disease & valves dont close completely -> leak/regurgitation

Front 191

regurgitation:

Back 191

back flow of blood:
aorta->LV, pulmonary trunk->RV, or LV->LA, RV->RA

Front 192

Structure & Fxn of Cardiac Musc Cells: Histology

Back 192

1.cross striations: b/c of sarcomeres- actin, myosin, myofilaments
2.1 nucleus/cell
3.cytoplasm banches
4.intercalated discs where 2 cardiac musc cells connect & gap jxns present here allowing for AP to move quickly from one cell to another

Front 193

Structure & Fxn of Cardiac Musc Cells: Functional Syncytium

Back 193

1 stimulus causes the entire structure of heart to react

Front 194

Structure & Fxn of Cardiac Musc Cells: All or None Law

Back 194

a stimulus =/> threshold stimuluates a heartbeat & stimulus < threshold leads to no rxn
-applies to entire heart, not indiv cells

Front 195

Structure & Fxn of Cardiac Musc Cells: AP

Back 195

.3 sec in heart (much slower than .002sec in sk.musc)
-RP @ 95mV, crosses threshold, AP to +25mV --> 120mV total voltage

Front 196

phases of AP:

Back 196

1.depolarization: Na entry
2.plateau phase: Kexit/Ca entry
3.repolarization: K exit
*absolute refractory period long & relative refractory period short

Front 197

absolute RP:

Back 197

.25sec; no other stim can stimulate AP during this time; heart cannot be summated/tetanized

Front 198

relative RP:

Back 198

.05sec following absolute; strong stim can cause 2nd heart beat; tetanized->attack

Front 199

electrical activity of heart as relates to cardiac cycle:

Back 199

1.sino-atrial node (SA node)
2.Atrio-ventricular node (AV node)
3.ventricular conducting system

Front 200

SA node:

Back 200

pacemaker;
1.located @ wall of RA near where sup vena cava enters
2.automatically depolarizes & sends AP to
3.Atrial conducting pathway

Front 201

automatically depolarizes-

Back 201

normal adult @ rest, SA node fires off 70-80 APs/min->governing HR

Front 202

atrial conducting pathway-

Back 202

nerve fiberlike braches; found in both L&RA; fxn:send APs to atrial myocardium & cause atrial systole

Front 203

AV node:

Back 203

located at base of RA b/w RA & RV; receives AP from atrial conducting pathway

Front 204

AV node fxns:

Back 204

1.delays AP for fraction of a sec allowing time for completion of atrial diastole
2.transmisson of AP to ventricular conducting system

Front 205

ventricular conducting system:

Back 205

1.AV bundle:bundle of his; nervelike structure in interventricular septum; spilts in 2:
2.L&R bundle branches in septum
3.purkinje fibers: nervelike fibers found in all regions of both ventricles

Front 206

perkinje fibers fxn:

Back 206

get AP to all regions of ventricles quickly & simultaneously

Front 207

electrocardiogram:

Back 207

all electrical activity assoc w/ 1 heartbeat

Front 208

EKG: basis

Back 208

ap from heart->tranferred to body fluids->conduct electrical act thruout whole body up to skin->attach electrodes to ankles, wrists, areas over chest, electrical signals detected by electrodes

Front 209

EKG: pattern

Back 209

1. p wave
2. qrs complex
3. t wave
4. 2 intervals

Front 210

p wave:

Back 210

represents atrial depolarization, resulting in atrial systole

Front 211

qrs complex:

Back 211

ventricular dep, resulting in ventricular systole

Front 212

t wave:

Back 212

ventricular rep, resulting in ventricular diastole

Front 213

2 intervals:

Back 213

1.P-R interval: time it takes for single AP to move from SA->AV node
2.Q-T interval: all electrical act of ventricles (dep & rep)

Front 214

EKG: value

Back 214

diagnostic tool in that it allows us to det HR & if any abnorm conduction of AP thru the heart

Front 215

normal HR

Back 215

70-80 bpm

Front 216

arrhythmias:

Back 216

any condition that alters normal heart rhythm
1.alterations in SA node act
2.Ectopic Foci

Front 217

alterations in SA node act:

Back 217

1.bradycardia
2.tachycardia

Front 218

bradycardia

Back 218

-HR of 60bpm/less
1.trained athletes
2.untrained myxedema

Front 219

bradycardia: trained athlete

Back 219

heart musculature builds up and they contain large SV; need higher HR, so undergo bradycardia during sleep

Front 220

bradycardia: untrained myxedema

Back 220

hypothyroidism; abnormally slow HR; result of excess use of beta blockers (drug)

Front 221

tachycardia

Back 221

HR =/> 100bpm; results from normal exercise, hypotension: BP too low, so inc HR to compensate pumping blood to body, severe anxiety/stress, excess use nicotine

Front 222

Ectopic Foci

Back 222

creation of abnormal pacemakers that become governing body of HR over pacemaker SA node

Front 223

Ectopic Foci: most common cause

Back 223

localized ischemia:lack of blood supply to regions of heart; also results from excess use of nicotine, caffeine

Front 224

Ectopic Foci: Effects

Back 224

1.single EF, PVC
2.single EF, Flutter
3.multiple EFs

Front 225

single EF, PVC

Back 225

pre-ventricular contraction; initiate AP->stimulates 1 HB out of order (typically caused by caffeine, not seriuos)

Front 226

single EF, Flutter

Back 226

300bpm; HBs coordinated, but pumping action inefficient: heart not allowed to fill to full volume, so not pumping otuput normally

Front 227

multiple EFs

Back 227

multiple pacemakers indpt of one another & coordination of HBs lost; muscle has no pumping action @ all

Front 228

atria fibrillation:

Back 228

atria dont contract in coordination; ventricles contract irregularly, but ventricular contraction capable of sustaining life; inefficient pump all together

Front 229

ventricular fibrillation:

Back 229

coronary thrombosis (blood clot)occurring in coronary artery, leads to local ischemia, resulting in:

Front 230

vent. fibrillation results in:

Back 230

1.myocardial infarction: death of cardiac ventricular musc
2.multiple EF: prevents vent from contracting in norm manner-> no pumping action in vent & if severe enough, >6min, leads to death due to lack of blood supply to brain

Front 231

interference of AP conduction thru heart:

Back 231

damage to AV node, bundle of his, or L/R bundle branches compromise AP conduction
1.heart block
2.myocardial infarction

Front 232

heart block:

Back 232

atria beat @ faster rate than ventricles due to improper/blocked input of AP to vent

Front 233

myocardial infarction:

Back 233

necrosis of ventricular myocardium & replaced w/ scar tissue -> conduction of AP slower than norm

Front 234

Cardiac Physiology:

Back 234

1.Cardiac Output
2.BVs

Front 235

Cardiac Output

Back 235

volume of blood pumped out of the heart each min

Front 236

Cardiac Output: determining factors

Back 236

1.SV-volume blood ejected w/ systole (avg 72ml/min)
2.HR- avg 75bpm
3.CO=SV*HR- avg 5.4 L/min @ rest & can inc as high as 30 L/min during exercise due to inc SV & inc HR

Front 237

Cardiac Output: factors controlling change of CO

Back 237

1.intrinsic autoregulation/starlings law of the heart
2.nervous reflex control of CO

Front 238

intrinsic autoregulation/starlings law of the heart

Back 238

the greater the vol blood entering during diastole, the greater the bol blood pumped out during systole

Front 239

intrinsic autoregulation mechanisms:

Back 239

1.venous return:vol of blood returning to RA from sup/inf vena cava each min

Front 240

increased venous return->

Back 240

greater stretchon vetnricular myocardium-> muscle responds to stretch w/ myocardium inc force of conraction -> inc SV -> inc CO (start w/ > coming in, end w/ > going out)

Front 241

nervous reflex control of CO

Back 241

1.parasymp innervation
2.vagal tone
3.symp innervation
4.mechanisms of action

Front 242

parasymp innervation:

Back 242

L&R vagus nerves (2) innervate the heart & use Ach as NT
-Rvagus nerve supplies SA node
-Lvagus nerve supplies AV node
-both send FEW fibers to ventricular myocardium

Front 243

vagal tone:

Back 243

continual, low level vagal input to heart; few APs come to this region & this keeps heart at norm rate of act/slows it

Front 244

symp innervation:

Back 244

T1-T6 spinal nerves (6) innervate the heart & release NE as NT; all supply SA node, AV node, & vent myocardium

Front 245

mechanisms of action:

Back 245

1.alterations of HR
2.alterations of contractile forces of heart

Front 246

alterations of HR

Back 246

-inc parasymp input largely & dec act of SA node->dec HR-> dec CO
-inc symp input & inc SA node act-> inc HR-> inc CO

Front 247

alterations of contractile forces of heart

Back 247

-inc symp stimulation-> inc force of contrxn to vent myocardium-> inc SV-> inc CO (strong effect)
-inc parasymp stimulation-> slight dec force of contrxn to vent myocardium-> slight dec SV-> slight dec CO

Front 248

pathological conditions altering CO:

Back 248

1.prob w/ heart valves leading to valvular insufficiency: blood flows backward a/g norm flow -> dec SV-> dec CO
2.stenosis: in bicuspid valve; dec SV-> dec CO
3.anemia: lack of O2 carrying capacity in blood; tissues in body dont receive adequate blood supply-> inc HR-> inc CO

Front 249

Cardiac Physiology: BVs

Back 249

3 layers make up BV wall:
1.Tunica Adventitia/Externa: outer layer, CT
2.Tunica Media: middle layer, smooth musc
3.Tunica Interna/Intima: innermost layer, in contact w/ blood, made of endothelium tissue->very smooth tissue preventing blood clotting inside BV

Front 250

BV: types

Back 250

1.elastic arteries
2.muscular arteries
3.arterioles
4.metaarterioles
5.capillaries
6.venules
7.veins

Front 251

elastic arteries:

Back 251

contain elastic CT in them @ walls; begin @ aorta, branches to include brachiocephalicA, subclavians, common carotids, common iliac A; do not collapse

Front 252

muscular arteries:

Back 252

no elastic CT; ext/int carotids, brachials, subscapulars, radial/ulnar A, ext/int iliacs, femoral, deep femoralA; do not collapse

Front 253

arteries subdivide into smaller arteries: arterioles

Back 253

smaller diameter; tunica media decreased

Front 254

metarterioles:

Back 254

connect arterioles to venules w/o forming capillaries

Front 255

capillaries:

Back 255

-no tunica externa or media
-single layer of endoth cells only
-derived from aterioles or metarterioles
-allows for exchange of materials b/w blood & body fluids

Front 256

capillary divisions:

Back 256

1.continuous: no openings in walls; most common
2.fenestrated: opening in walls/pores; found in kidneys
3.sinusoids: very large pores; found in spleen & liver

Front 257

venules:

Back 257

formed by fusion of capillaries; walls not as thick, but similar to arterioles; diameter larger than arterioles

Front 258

veins:

Back 258

formed by fusion of venules; wall thickness less & diameter larger than artery; vein walls collapsable due to much less smooth musc in vein wall than artery wall

Front 259

vein: blood reservoir

Back 259

in normal conditions, veins hold up to 59% of total blood volume; larger veins have internal valves-found in arms, legs, inf vena cava

Front 260

BV fxns: arteries & arterioles

Back 260

transport blood (usually oxygenated, but not always) FROM heart; EXCEPT pulmonary trunk & arteries carry deoxygenated blood from heart

Front 261

BV fxns: elastic arteries

Back 261

1.provide pulse wave: blood enters aorta under press->aorta expands during systole->elastic elements retract aorta to norm pos w/ following diastole causing HB

Front 262

pulse path:

Back 262

starts in aorta, then transported to all elastic & muscular arteries, to radial artery for you to det pulse/HR

Front 263

BV fxns: arterioles

Back 263

diameter changes easily w/autonomic stimulation -> major BP regulators in body

Front 264

BV fxns: capillaries

Back 264

exchange of substance b/w blood plasma & tissue fluids

Front 265

BV fxns: venules & veins

Back 265

carry blood (usually deoxygenated) TO heart; EXCEPT pulmonary veins carry oxygenated blood to heart

Front 266

BV fxns: large veins

Back 266

arms & legs; contain valves that help prevent backflow of blood in veins
1.muscular pump

Front 267

muscular pump:

Back 267

1.musc contrxns "squeeze" vein & cause blood to move
2.musc relaxation removes compression/press off vein & cause blood to flow backward->valves close & prevent regurgitation maintaing blood flow toward heart

Front 268

BV: general plan circulation

Back 268

LA->LV->aorta->coronary sys OR systemic sys->arteries->arterioles->capillaries->venules->veins->vena cava (sup or inf)->RA->RV->pulmonary trunk of pulmonary sys->arteries->arterioles->capillaries->venules->veins->LA

Front 269

blood flow systems:

Back 269

start & come back to LA; flow thru 3 systems:
1.coronary sys: supplies heart
2.systemic sys: supplies all parts of body except heart & lungs
3.pulmonary sys: supplies lungs

Front 270

BV: blood pressures in systemic circulation

Back 270

goes to every part of body BUT lungs/heart;
1.systolic pressure
2.diastolic pressure
3.pulse pressure
4.mean arteriol pressure

Front 271

systolic pressure:

Back 271

pressure exerted on aorta & arteries during vetnricular systole
-@ rest 120 mmHg

Front 272

diastolic pressure:

Back 272

pressure exerted on aorta & arteries during ventricular diastole
-@ rest 80 mmHg

Front 273

pulse pressure:

Back 273

difference b/w SP & DP
-@ rest 120-80= 40 mmHg
-faint pulse lower 40 mmHg ->heart not beating as strong

Front 274

mean arterial pressure (MAP)

Back 274

BP; average of SP & DP 120+80=200/2 = 100 mmHg in aorta
1.driving force of blood thru BVs
2.force that causes fluid exchng in blood capillaries
3.as move further away from heart, MAP dec b/c BVs cause resistance to blood flow-> pressure dec
*by time reaches arterioles, 55% of resistance has occurred

Front 275

BV: regulation of MAP

Back 275

1.MAP=CO*PR (peripheral resistance: resistance to flow in BVs)
2.direct relationships: inc CO-> inc MAP & inc PR-> inc MAP

Front 276

main factors determining PR

Back 276

1.viscosity of blood: thickness; high viscosity->high PR-> high BP; low viscosity-> low PR-> low BP
2.diameter of arterioles: very impt b/c arterioles major BP regulators

Front 277

diameter of arterioles:

Back 277

1.control center: vasomotor center in MO; sends out symp impulses to smooth musc arterioles
2.vasomotor tone

Front 278

vasomotor tone:

Back 278

continual output; few in #; maintain arteriole smooth musc partially contracted state

Front 279

vasomotor deviations:

Back 279

1.inc output from VM center->vasoconstriction-> inc PR
2.dec output from VM center->vasdilation->dec PR

Front 280

regulatory mechanisms related to PR

Back 280

1.vasomotor baroreflex
2.vasomotor chemoreflex

Front 281

vasomotor baroreflex:

Back 281

change in pressure causing reflex;
found in aortic arch & carotid sinus;
-aortic receptors connected to VM center by vagus nerve
-carotid receptors connected to VM center by glossopharyngeal nerve

Front 282

vasomotor chemoreflex:

Back 282

change in O2/CO2 press in arterial blood, pH;
found in aortic arch (vagus nerve concxn)& int carotid A (glossop. concxn)