Cardiac

Question 1

define blood pressure

Answer 1

force on the blood vessel walls

Question 2

periods of relaxation in the heart are called …

Answer 2

diastole

Question 3

periods of contraction are called …

Answer 3

systole

Question 4

what are the 2 AV valves called

Answer 4

bicuspid
tricuspid

Question 5

location of the bicuspid valve

Answer 5

left side

Question 6

location of tricuspid valve

Answer 6

right side

Question 7

how do AV valves work to prevent back flow of blood

Answer 7

as ventricles contract, blood tries to move back to the atria.
the blood gets caught in the pockets of the valves and pushes them shut

Question 8

what muscles contract preventing valves folding back into the atria under high pressure

Answer 8

papillary muscles and they pull on heart strings

Question 9

two semilunar valves are called

Answer 9

aortic valve
pulmnary valve

Question 10

how do the semilunar valves work to prevent back flow of blood

Answer 10

as pressure falls in ventricles, blood tries to flow back from aorta and pulmonary artery into the ventricles
the semilunar valves fill with blood and the bulge prevents back flow

Question 11

what is the function of papillary muscles

Answer 11

to contract and pull on the heart strings which resists pressure of blood forcing valves to turn inside out when ventricles contract

Question 12

describe blood flow on the right side

Answer 12

vena cavae
right atrium
tricuspid valve
right ventricle
pulmonary semi lunar valve
pulmonary artery

Question 13

describe blood flow on the left side

Answer 13

pulmonary vein
left atrium
bicuspid valve
left ventricle
aortic semilunar valve
aortic artery

Question 14

describe the pulmonary circuit

Answer 14

right ventricle
pulmonary artery
capillary beds of lung
pulmonary vein
left atria

Question 15

describe the systematic circuit

Answer 15

left ventricle
aorta
capillary beds of body tissues
vena cava
right atrium

Question 16

what is the function of the coronary circulation

Answer 16

to supply blood to the heart as the heart muscle is too thick to allow diffusion

Question 17

where does the coronary circulation originate

Answer 17

oxygenated blood from the aorta

Question 18

where does the coronary circulation terminate

Answer 18

right atrium as the blood will be deoxygenated and ready to go back to the lungs

Question 19

what is meant by intrinsic conduction system

Answer 19

internal conduction system

Question 20

basic rythym of intrinsic conduction system

Answer 20

100 beats per minute

Question 21

how is heart rate modified by neural innervation

Answer 21

the SA and AV nodes are connected by parasympathetic and sympathetic nerves, they slow down and speed up the nerves

Question 22

how is the heart rate modified by hormonal influences

Answer 22

adrenaline and thyroxine are released into the blood and circulate to stimulate the heart directly

Question 23

what are the 3 major events of the cardiac cycle

Answer 23

atrial and ventricle diastole
atrial systole and ventricle diastole
atrial diastole and ventricular systole

Question 24

define stroke volume

Answer 24

volume of blood ejected from the heart per beat

Question 25

define cardiac output

Answer 25

volume of blood pumped out the heart per minute

Question 26

define preload

Answer 26

degree of stretch on the ventricle walls by blood return

Question 27

what effect does an increase in preload cause

Answer 27

actin and myosin are in a better position to form cross bridges generating greater force

Question 28

what effect does generating more force through preload cause

Answer 28

increases stroke volume and therefore cardiac output

Question 29

define afterload

Answer 29

degree of stretch on the ventricle walls caused by pressure within the blood vessels leaving the heart

Question 30

what effect does an increase in afterload cause

Answer 30

sarcomeres can become overstretched which reduces the ability to form cross bridges

Question 31

what effect does reducing the force cause

Answer 31

decreases stroke volume and therefore cardiac output

Question 32

define contractility

Answer 32

force of contraction at a given length of muscle

Question 33

what effect does calcium cause on contractility

Answer 33

exposes more actin binding sites allowing more cross bridge formation

Question 34

what 2 things increase cardiac output

Answer 34

increase in preload
increase in contractility

Question 35

what decreases cardiac output

Answer 35

increasing afterload

Question 36

what does the p wave show

Answer 36

atrial systole

Question 37

what does the QRS wave show

Answer 37

venricular systole and atrial diastole

Question 38

what does the T wave show

Answer 38

ventricle diastole