Ch. 12

Question 1

aortic semilunar valve

Answer 1

prevents back flow from the blood moving from the left ventricle to the aorta

Question 2

aorta

Answer 2

branches and carries blood away from the heart to all organs and tissues in the systematic circuit

Question 3

tricuspid valve

Answer 3

prevents back flow of blood traveling from the right atrium to the right ventricle

Question 4

pulmonary semilunar valve

Answer 4

prevents back flow of blood traveling from the right ventricle to the pulmonary artery

Question 5

pulmonary artery

Answer 5

the only artery carrying deoxygenated blood and goes to the lungs to drop off CO2

Question 6

where is blood oxygenated?

Answer 6

in the lungs

Question 7

where does the blood go after is it oxygenated?

Answer 7

through the pulmonary vein to the left atrium

Question 8

pulmonary vein

Answer 8

the only vein in the body carrying oxygenated blood

Question 9

bicuspid valve

Answer 9

prevents back flow of blood traveling from the left atrium to the left ventricle

Question 10

where does the blood enter the heart?

Answer 10

through the vena cava (biggest vein)

Question 11

where does the blood leave the heart

Answer 11

through the aorta (biggest artery)

Question 12

venules

Answer 12

the small vessels transporting blood to the heart

Question 13

Cardiac cycle

Answer 13

the atria contracts first which forces blood into the ventricles, then the ventricles contract forcing blood into the arteries

Question 14

pacemaker cells

Answer 14

sets the rhythm of the heartbeat, produces AP that causes the heart to contract

Question 15

myogenic

Answer 15

means that our heart contracts because of the cell not because we think about making our heart contract

Question 16

gap junctions

Answer 16

when one cell gets response it allows for all the cells in the heart to receive the same response allowing the heart to contract together

Question 17

cardiac conduction fibers

Answer 17

transmits rhythm of heartbeat and carries the AP to every other area on of the heart

Question 18

where are the pacemaker cells found?

Answer 18

on the SA and AV nodes

Question 19

where are the cardiac conduction fibers found?

Answer 19

on the intermodal and interatrial pathways and Purkinje fibers

Question 20

cardiac contractile cells

Answer 20

generate the contractile force

Question 21

what does the SA node do?

Answer 21

it is where the AP is initiated

Question 22

what does the AV node do?

Answer 22

slows down the conduction of the AP so that the atria has time to completely contract before the ventricle begins to contract

Question 23

what causes the funny channels to open?

Answer 23

hyperpolarization of the membrane

Question 24

what happens when the funny channels open?

Answer 24

more permeable to Na than K; cell becomes more positive; causes depolarization

Question 25

what happens when funny channels close?

Answer 25

T-type Ca channels open causing the potential to reach threshold (the point of no return)

Question 26

systole

Answer 26

ventricular contraction

Question 27

diastole

Answer 27

ventricular relaxation

Question 28

T type Ca channels

Answer 28

helps the membrane to reach threshold; cell is now more permeable to Ca than Na; closes once it reaches threshold

Question 29

rapid depolarization

Answer 29

L type Ca channels and Na channels are open causing the cell to become very positive quickly

Question 30

peak of AP (repolarization)

Answer 30

L type Ca channels and Na channels are closed and K channels are open so the cell returns to a negative potential

Question 31

L type Ca channels

Answer 31

allow for the cell to have a long duration AP

Question 32

relaxed muscle fibers

Answer 32

tropomyosin blocks myosin-binding sites

Question 33

what happens when Ca binds to troponin?

Answer 33

the tropomyosin is moved exposing the myosin binding sites so they muscle can contract

Question 34

when are the AV valves open?

Answer 34

when the pressure in the atria is higher than the pressure in the ventricles

Question 35

when are the AV valves closed?

Answer 35

when the pressure in the ventricles is higher than the pressure in the atria

Question 36

when are both semilunar valves open?

Answer 36

when the pressure in the ventricles is higher than the pressure in the arteries

Question 37

when are both semilunar valves closed?

Answer 37

when the pressure in the arteries is higher than the pressure in the ventricles

Question 38

aortic and pulmonary semilunar valves

Answer 38

are found separating the ventricles from the arteries that come out of them

Question 39

ventricular filling

Answer 39

blood from systemic and pulmonary circuits flow through atria into ventricles; AV valves are open and SL valves are closed; part of diastole because ventricles are relaxed

Question 40

atrial contraction

Answer 40

at the end of diastole, atria contract, driving more blood into the ventricles; atria begin to relax

Question 41

isovolumetric contraction

Answer 41

ventricles begin to contract (systole) so the pressure is rising because AV and SL valves are closed

Question 42

ventricular ejection

Answer 42

ventricles are contracting (systole); AV valves are closed and SL valves are open; opening SL valves allows ventricles to eject their contents into the systemic and pulmonary circuits

Question 43

isovolumetric relaxtion

Answer 43

ventricles relaxing (diastole); AV and SL valves are closed