The Heart

Question 1

the heart structure

Answer 1

hollow, cone shaped muscular double pump

Question 2

heart location

Answer 2

within the thorax and resting upon the diaphragm

Question 3

heart size

Answer 3

12 cm x 9 cm x 6 cm

weighs 10 oz

Question 4

heart base

Answer 4

the top, wide posterior part lies beneath the 2nd rib

Question 5

pericardium

Answer 5

3 layered sac around the heart

Question 6

fibrous pericardium

Answer 6

the most outer tough, inelastic layer made of fibrous connective tissue

Question 7

serous pericardium

Answer 7

has 2 layers that are connected inside the fibrous pericardium

Question 8

outer parietal layer

Answer 8

outer layer of the serous pericardium

Question 9

pericardial cavity

Answer 9

chamber between the outer-parietal layer and inner-visceral layer

Question 10

inner-visceral layer

Answer 10

inner layer of the serous pericardium

also called the epicardium

Question 11

walls of the heart

Answer 11

epicardium, myocardium, and endocardium

Question 12

epicardium

Answer 12

also the inner-visceral layer of the pericardium
function: protective layer
consists of connective tissue

Question 13

myocardium

Answer 13

thickest wall of the heart
function: pumping action
consists of cardiac muscle tissue which are separated by connective tissue

Question 14

endocardium

Answer 14

inner wall of the heart
contain epithelial tissue, connective tissue, and the connective tissue specializes in cardiac muscle fibers called purkinje fibers

Question 15

2 upper chambers of the heart

Answer 15

right and left atrium

receive the blood

Question 16

2 lower chambers of the heart

Answer 16

right and left ventricle
pump out the blood
right ventricle is thinner

Question 17

auricles

Answer 17

above the atriums and increase the volume of the atria

Question 18

intraventricular septum

Answer 18

separates the right and left ventricles

Question 19

interatrial septum

Answer 19

separates the right and left atriums

Question 20

coronary sulcus

Answer 20

separates the atria from the ventricles

Question 21

what is a heart valve

Answer 21

what guards the opening between an atrium and its corresponding ventricle to protect the back flow of blood

Question 22

2 atrioventricular valves (AV)

Answer 22

tricuspid valve (right)
bicuspid or mitral valve (left)

Question 23

2 semilunar valves

Answer 23

valves leading out of the heart
pulmonary sl valve (right)
aortic sl valve (left)

Question 24

chordae tendineas

Answer 24

strong, fibrous string attached to the cusps of the AV valves and is connected with small mounds of papillary muscles on the surface of the ventricles

Question 25

AV valve when relaxed

Answer 25

papillary muscle: relaxed chordae tendineas: slack valve: open

Question 26

AV valve when contracting

Answer 26

papillary muscle: contract chordae tendineas: taught valve: closed

Question 27

intrinsic cardiac conduction system

Answer 27

impulse at: 1. sinoatrial node 2. atrioventricular node 3. bundle branches 4. subendocardial conducting network or pukinje fibers

Question 28

ECG

Answer 28

a composite action potentials produced by the heart muscles during each heart beat (70-80/min)

Question 29

P phase

Answer 29

caused by depolarization of atrial fibers just before contract when impulses move from SA to AV node

Question 30

QRS complex

Answer 30

represent the spread of depolarization through the bundle of His and ventricular wall during contraction

Question 31

T phase

Answer 31

represents electrical recovery and relaxation (repolarization) of ventricles

Question 32

if you enlarge p-phase

Answer 32

increase the size of the atrium

Question 33

if you enlarge Q phase

Answer 33

myocardial infarction/heart attack

Question 34

if you enlarge R phase

Answer 34

increase size of the ventricles

Question 35

if S-T are elevated above the baseline

Answer 35

acute myocardial infarction

Question 36

if S-T are depressed or flatter T

Answer 36

decreasing O2

Question 37

cardiac cycle

Answer 37

the events of one complete heart rate during which both atria and ventricles contract and relax 72/min .8 sec/cycle

Question 38

systole

Answer 38

.3 second contraction

Question 39

diastole

Answer 39

.4 sec relaxation

Question 40

ventricular systole

Answer 40

contraction impulse->AV node->ventricles depolarize (QRS) pressure increases in ventricles, AV valve closes (.05 sec), for .25 sec both SL valves open and eject blood

Question 41

end systolic volume

Answer 41

60 mL left in each ventricle

Question 42

relaxation period + ventricular filling

Answer 42

at the end of the beat (T wave) ventricles relax and all 4 chambers are in diastole, (.4 sec) back flow of blood causes SL valves to close, pressure goes down allowing AV valve to open and rapid filling.

Question 43

atrial contraction

Answer 43

SA node results in depolarization of atria (P wave), atria contracts (.1 sec) and more blood flows in ventricles. Sl valves are closed. Atrial systole contributes to only 20-30% of total blood volume.

Question 44

heart circuit

Answer 44

``` left ventricle aortic valve aorta systemic arteries systemic circuit systemic veins venae cavae right atrium tricuspid valve right ventricle pulmonary valve pulmonary arteries capillaries lung pulmonary veins left atrium bicuspid valve ```

Question 45

heart sounds

Answer 45

lubb dupp

Question 46

what is the lubb sound caused by

Answer 46

closing of the AV valves

Question 47

what is the dupp sound caused by

Answer 47

when SL valves closes at the end of systole

Question 48

heart sound 3

Answer 48

not loud enough to hear | associated with rapid ventricular filling

Question 49

heart sound 4

Answer 49

not loud enough to hear | associated with atrial contraction

Question 50

heart murmur

Answer 50

are abnormal or unusual heart sounds due to valvular defects | common in young children and old people

Question 51

where heart sounds heard

Answer 51

1. aortic valve (top right) 2. tricuspid valve (bottom right) 3. pulmonary valve (top left) 4. mitral valve (bottom left)

Question 52

cardiac output

Answer 52

the amount of blood pumped out of each side of the heart (each ventricle) in one minute HR x SV = CO

Question 53

stroke volume

Answer 53

the volume of blood pumped out by a ventricle with each heart beat.

Question 54

normal resting stroke volume

Answer 54

70 mL/beat

Question 55

average adult cardiac output

Answer 55

5.25 L

Question 56

normal blood volume

Answer 56

5-6 L

Question 57

the vagus nerve

Answer 57

decreases heart rate | parasympathetic

Question 58

sympathetic cardiac nerve

Answer 58

increases heart rate increases stroke volume will make heart contract stronger