Chapter 9

Question 0

Blood vessels

Answer 0

Passageways through which blood is distributed from heart to all parts of the body and back to the heart.

Question 1

Heart

Answer 1

Serves as a pump that establishes the pressure gradient needed for blood to flow to tissues.

Question 2

Blood

Answer 2

Transport medium within which materials being transported are dissolved and suspended

Question 3

Pulmonary circulation

Answer 3

Closed loop of vessels carrying blood between heart and lungs

Question 4

Systemic circulation

Answer 4

Circuit of vessels carrying blood between heart and other body parts.

Question 5

Atrioventricular valves

Answer 5

Right and left AV valves positioned between atrium and ventricle on right and left sides.

Prevent backflip of blood from ventricles into atria during ventricular emptying.

Question 6

Right AV valve

Answer 6

Tricuspid valve

Question 7

Left AV valve

Answer 7

Bicuspid/mitral valve

Question 8

Chordae tendinae

Answer 8

Fibrous cords which prevent valves from being everted. Papillary muscles

Question 9

Semilunar valves

Answer 9

Aortic and pulmonary valves.
Lie at juncture where major arteries leave ventricles.

Prevented from everting by anatomic structure and positioning of cusps.

Question 10

Endothelium

Answer 10

Thin inner tissue.

Epithelial tissue, lines entire circulatory system.

Question 11

Myocardium

Answer 11

Middle layer, cardiac muscle.

Constitutes bulk of heart wall.

Question 12

Epicardium

Answer 12

Thin external layer which covers heart.

Question 13

Cardiac muscle fibers

Answer 13

Interconnected by intercalated discs and form functional syncytia.

2 kinds of membrane junctions: desmosomes
Gap junctions

Question 14

Autorhythmicity

Answer 14

Heart beats via

Question 15

Contractile cells

Answer 15

99% of cardiac muscle cells
Do mechanical work of pumping
Normally don’t initiate action potentials

Question 16

Autorhythmic cells

Answer 16

Do not contract

Specialized for initiating and conducting action potentials responsible for contraction of working cells.

Question 17

Myocardial aps

Answer 17

RMP of -90mV

Depolarized to threshhold by APs originating in SA node.

Question 18

Systole

Answer 18

Contraction heart phase

Question 19

Diastole

Answer 19

Relaxation phase of the heart

Question 20

End-diastolic volume

Answer 20

Volume of blood in ventricles at end of diastole

Question 21

Stroke volume

Answer 21

Amount of blood ejected from ventricles during systole

Question 22

End-systolic volume

Answer 22

Amount of blood left in ventricles at end of systole

Question 23

Parasympathetic stimulation

Answer 23

Slows heart rate

Question 24

Sympathetic stimulation

Answer 24

Speeds heart rate up