Heart Basics

Question 1

what is the heart physiology

Answer 1

a muscular pump

Question 2

where is the heart located

Answer 2

in the thoracic cavity (mediastinum)

Question 3

what is the heart between

Answer 3

the 2nd and 5th ribs

Question 4

is the heart on the midline

Answer 4

about 2/3 left of the midline

Question 5

size of heart

Answer 5

size of fist

Question 6

anatomical angle of heart

Answer 6

45 degrees

Question 7

what are the layers of the heart (3)

Answer 7

epicardium, myocardium, and endocardium

Question 8

epicardium is also called what

Answer 8

visceral pericardium

Question 9

what is myocardium and what does it function

Answer 9

cardiac muscle tissue
it contracts to produce force to push blood throughout vasculature

Question 10

what “skeleton” is in myocardium

Answer 10

fibrous skeleton

Question 11

what makes up the fibrous skeleton

Answer 11

elastic and collagen fibers

Question 12

collogen functions in the fibrous skeleton

Answer 12

provide physical support to cardiac m. cells
distributes force fo contraction
reinforces valves and openings to b.v
prevent over expansion of heart

Question 13

elastic functions in the fibrous skeleton

Answer 13

returens heart to original shape after contraction

Question 14

is the myocardium layer striated

Answer 14

yes, this is a regular arrangement of actin and myosin where ends of each overlap. the molecules themselves are parallel

Question 15

what are intercalated discs in the myocardium

Answer 15

are between adjacent cells. are interlocking membranes

Question 16

desmosomes def

Answer 16

cell junctions reinforced by intermediated filaments

Question 17

gap junctions def

Answer 17

pores that allow for ions movement, the heart chambers to contract as syncytium.

Question 18

what type of connective tissue is endocardium

Answer 18

loose/areolar CT

Question 19

what cells are in endocardium

Answer 19

simple squamous epithelium

Question 20

what is endocardium continuous with

Answer 20

epimysium

Question 21

what does the simple squamous epithelium in endocardium allow for in related to blood flow

Answer 21

decreases friction to blood flow

Question 22

What are the 3 main parts of the pericardial sac

Answer 22

parietal pericardium
visceral pericardium
pericardial cavity

Question 23

what is the pericardial sac

Answer 23

a protective covering that surrounds the heart

Question 24

what are the 2 layers of parietal pericardium

Answer 24

fibrous layer and serous layer

Question 25

information on the fibrous layer of the parietal pericardium Location, type of tissue, fucntion

Answer 25

superficial, and anchors heart to diaphragm and ribs dense irregular ct protects heart from over expanding

Question 26

information on the serous layer of the parietal pericardium cell type function

Answer 26

simple squamous epithelial cells secretes srous fluid into pericardial space. a lubricant .

Question 27

what is between the fibrous and serous layer

Answer 27

vascular aereolar CT

Question 28

what layer is within visceral pericardium

Answer 28

serous layer

Question 29

information on the serous layer of the visceral pericardium cell type, function, facing what

Answer 29

simple squamous ephithelium, sercretes fluid facing pericardium cavity

Question 30

function of the pericardial cavity

Answer 30

is wehre the fluid secreted by the 2 serous layers collects. decreases friction

Question 31

does the right side of the heart deal with oxygenated or deoxygenated blood

Answer 31

deoxygenated

Question 32

does the left side of the heart deal with oxygenated or deoxygenated blood

Answer 32

oxygenated

Question 33

what is the pulonary circulation

Answer 33

right side of heart low oxygen high co2 heart and lungs

Question 34

what is systemic circulation

Answer 34

left side of heart high oxygen low co2 heart and rest of body

Question 35

pulonary ciruclation order starting in RA

Answer 35

right atrium, right ventricle, pulmonary trunk/arteries (R/L), branching to pulmonary capillaries , converging to pulmonary veins (R/L), then left atrium.

Question 36

what happens at pulonary capillaries

Answer 36

at lungs do gas exchange

Question 37

order of systemic circulation starting in LA

Answer 37

left atrium, left ventricle, aorta, systemic capillaires, superior/inferior vena cava, and right atrium

Question 38

what happens at systemic capillaries

Answer 38

picking up CO2 and delivering O2

Question 39

what does the "hole in the heart" refer to and what are the 2 examples

Answer 39

hole in tissue between R/L atrium foramen ovale to fossa ovale and ductus arteiosus to ligumentum arteriosum

Question 40

single drop of blood pathway starting at Right atrium

Answer 40

RA, RV, pulatory trunk, R/L pulmatory arteries, pulatory capillaries, pulatory veins, LA, LV, aorta, systemic capillaries, superior or inferior vena cava,, back to RA

Question 41

What do heart valves do

Answer 41

prevent back flow of blood

Question 42

what are the 2 types of heart valves

Answer 42

atrioventricular valves and semilunar valves

Question 43

what are the two types of AV valves

Answer 43

Right/left AV valves

Question 44

where are AV valves located

Answer 44

betweeen atria and ventricle

Question 45

right AV valve, tricuspid or bicuspid

Answer 45

tricuspid

Question 46

left AV valve, tricuspid or bicuspid

Answer 46

bicuspid

Question 47

what do chordae tendonae and papillary muscle do

Answer 47

prevent the prolapse of a valve (AV valve)

Question 48

how many cusps do semilunar valves have

Answer 48

3

Question 49

what are the 2 semilunar valves

Answer 49

pulmonary SL valve aortic SL valve

Question 50

when do SL valves open

Answer 50

when ventricular pressure exceeds artery pressure

Question 51

what do SL valves push blood into

Answer 51

artery

Question 52

when do SL valves close

Answer 52

when ventricular pressure drops below artery pressure

Question 53

when do AV valves close

Answer 53

when ventriccular pressure exceeds atrial pressure

Question 54

what is the mitral valve

Answer 54

AV valve between LA and LV

Question 55

what is mitral regurgitation called and means what

Answer 55

leaky valve/heart murmur when the valve isnt sufficient to prevent the backflow fo blood and decreases the efficiency of the heart

Question 56

what is mitral stenosis occur when and can lead to what

Answer 56

the narrowing of valve could be because of scar tissue or plaque build up can lead to hypertension

Question 57

how does valve replacement happen

Answer 57

open heart surgery can replace with mechanical, biological, or rubbery made valve. no option is perfect

Question 58

what is the NS role in the electrical system of heart

Answer 58

to speed up or slow down

Question 59

what is autorhythmicity

Answer 59

cardiac muscle self excites (contrcts without any external stimulation

Question 60

does the electrcal event precede or come after a mechanical event

Answer 60

precedes

Question 61

what is conducting system

Answer 61

cells responsible for initiating and distributing stimulus for heart to contract modified cardiac m. cells cause the cell membrane to not maintain a stable RMP/threshold. leads to more leaky to NA and fewer myofibirls and cells are smaller

Question 62

what is the normal resting heart rate

Answer 62

70 bpm

Question 63

what is affected in tonic inhibition

Answer 63

parasympathetic NS. at rest, the PSNS is firing and communicates with SA node by secreteing ACh

Question 64

what is the stress response

Answer 64

sympathetic NS SNS communicates with SA node via norepinephrine

Question 65

what do artificial pacemakes do

Answer 65

stimulate a regular heartbeat when the natural (SA NODE) electrical pacing system is irregular or not transmitting properly

Question 66

5 steps of the electircla system of the heart

Answer 66

atria fill, sa node self excites, depolarization. impuulse spreads via internodal fibers, and depolarize, then the impulse arrives at AV node and atria complete depolarization, they contract as a unit, the atria then repolarize and relax, the AP spread to L?R buncle branch, then the ventricles depolairze and contract

Question 67

pressure when AV valves close

Answer 67

ven pressure > atrial Pressure

Question 68

pressure when semilunar valves close

Answer 68

ven pressure< aorta pressure

Question 69

pressure when Av valves open

Answer 69

ven pressure < atrial pressure

Question 70

what happens during atrial fibuilation

Answer 70

no p wave, atrial muscel cells are depolarizing/contracting independent of one another