Lec 14- Cardiac System I

Question 1

Pulmonary

Answer 1

Closed loop circulation to the lung.

Question 2

Systemic

Answer 2

Circuit of vessels carrying blood between the heart abd the other body systems.

Question 3

Atria

Answer 3

Upper cambers of the heart that receive blood returning to the heart and deliver it to the lower chambers.

Question 4

Ventricle

Answer 4

Pump blood away from the heart.

Question 5

Septum

Answer 5

Separates the two halves of the heart.

Question 6

Myocardium

Answer 6

middle layer of the heart.

Question 7

Aorta

Answer 7

Carries oxygenated blood away from the heart to the body.

Question 8

Pulmonary artery

Answer 8

Carries partially deoxygenated blood from the heart to the lungs.

Question 9

Pulmonary vein

Answer 9

Returns oxygenated blood to the left atrium of the heart.

Question 10

AV valves

Answer 10

Valves between the atrium and ventricles.

Question 11

Tricuspid

Answer 11

Right AV valve.

Question 12

Bicuspid/mitral

Answer 12

Left AV valve.

Question 13

Semilunar valves

Answer 13

Aortic and pulmonary.

Each have 3 cusps resembling a shallow half-moon-shaped pocket.

Question 14

CO - cardiac output

Answer 14

volume of blood pumped by each ventricle per minute.

Question 15

SA (sinolatrial) node

Answer 15

A small, specialized region in the right atrial wall.
Fastest autorhythmicity at 70 to 80 AP’s per minute.
Is the pacemaker of the heart.

Question 16

Internodal pathway

Answer 16

extends from the SA node to the AV node.

Ensure sequential contraction of the ventricles following atrial contraction.

Question 17

AV (atrioventricular) node

Answer 17

Located at the base of the right atrium.

Only form of communication between the atria and ventricles.

Question 18

Bundle of His

Answer 18

A tract that starts from the AV node and travels through the septum out through the ventricles facing back to atrium

Question 19

Purkinje fibers

Answer 19

small fibers that extend form the bundle of his and spread throughout the ventricular myocardium.

Question 20

HCN - hyperpolarization activated cyclic-nucleotide gated.

Answer 20

aka funny channels.
spontaneous depolarization is caused by Na+ flwoing through channel that opens when hyperpolarized.
These unusual channels open when the potential becomes more negative (hyperpolarizes) at the end of repolarization from the previous AP.

Question 21

Absolute refractory period

Answer 21

Cannot be stimulated again, will not produce an AP.

Question 22

Plateau phase (Ca++)

Answer 22

Results from balance between slow Ca2+ influx and K+ efflux.

Question 23

SV - stroke volume

Answer 23

The amount of blood pumped out of each ventricle with each contraction.

Question 24

EDV - end diastolic volume

Answer 24

volume of blood in the ventricle at the end of diastole.

Question 25

Ejection Fraction

Answer 25

SV/EDV. | Normally is 60%; useful clinical diagnostic tool.

Question 26

Frank-Starling law of the heart

Answer 26

states that strength of ventricular contraction varies directly with EDV.

Question 27

Chronotropic effect

Answer 27

Influence heart rate

Question 28

Inotropic

Answer 28

Alters force of muscle contraction/strength.

Question 29

Intrinsic

Answer 29

Frank-Starling law of the heart is an intrinsic property of the myocardium.

Question 30

Extrinsic

Answer 30

FIND

Question 31

Skeletal Muscle Pump

Answer 31

Contraction of the skeletal muscle around the veins help push blood back up to the heart.

Question 32

Venous return

Answer 32

Venous return requires help from skeletal muscle pumps and one-way valves.

Question 33

Capacitance vessels

Answer 33

Veins hold 70% of blood in the body. | Have thin walls and stretch easily to accommodate more blood without increased pressure.

Question 34

Compliance

Answer 34

Veins have thin walls and stretch easily to accommodate more blood without increased pressure. Have higher compliance.

Question 35

Isovolumetric contraction

Answer 35

When all valves are closed, pressure builds up until it exceeds aortic pressure.

Question 36

Isovolumetric relaxation

Answer 36

All valves closed again. | Waiting for AV to open.

Question 37

Heart murmurs

Answer 37

Abnormal heart sounds produced by abnormal patterns of blood flow in the heart.

Question 38

Rheumatic fever

Answer 38

Secondary damage of this can cause mitral stenosis.

Question 39

Mitral Stenosis

Answer 39

Mitral valve is thickened and calcified. Vavle will not open fully.

Question 40

TPR - total peripheral resistance

Answer 40

impedance to blood flow in the arteries.