Ch. 42 - Circulation

Question 1

how do cells get the nutrients and oxygen they need?

Answer 1

diffusion and active transport

Question 2

what is the function of circulatory systems?

Answer 2

move oxygen and nutrients, remove wastes

Question 3

what is the function of arteries?

Answer 3

take blood away from the heart

Question 4

what are arterioles?

Answer 4

small arteries, near capillaries

Question 5

what is the function of veins?

Answer 5

bring blood towards the heart

Question 6

what are venules?

Answer 6

small veins, near capillaries

Question 7

what are atria?

Answer 7

chambers in the heart that receive blood

Question 8

where is blood delivered to in the systemic system?

Answer 8

to the tissues

Question 9

where is blood delivered to in the pulmocutaneous system?

Answer 9

to the lungs and skin

Question 10

where does the pulmonary system deliver blood to?

Answer 10

the lungs

Question 11

what is stroke volume?

Answer 11

the amount of blood pumped by the left ventricle per contraction, measured in mL/beat

Question 12

what is heart rate?

Answer 12

the number of beats per minute, measured by pulse

Question 13

what is cardiac output?

Answer 13

the volume of blood pumped by the left ventricle in one beat multiplied by the amount of beats in a minute

Question 14

what are the two kinds of heart valves?

Answer 14

2x atrioventricular valves; 2x semilunar valves

Question 15

what is a heart murmur?

Answer 15

a heartbeat sound caused by the heart’s valves not closing completely

Question 16

what is the SA node and what is its function?

Answer 16

the SA node creates the electrical impulse that drives the heartbeat, which also sets its pacemaker rhythm (~72 bpm)

Question 17

what is the route of travel through the cardiac conduction system?

Answer 17

1. SA node
2. AV node
3. AV bundle
4. bundle branches
5. purkinje fibers

Question 18

what causes blood pressure?

Answer 18

blood pressure is caused by the hydrostatic force exerted by blood on the wall of a vessel

Question 19

how is pulse pressure calculated?

Answer 19

systolic blood pressure - diastolic blood pressure

Question 20

what is peripheral resistance?

Answer 20

the resistance to blood flow in arterioles

Question 21

what process occurs at the arteriole end of a capillary?

Answer 21

hydrostatic pressure drives blood fluid into tissues

Question 22

what process occurs at the venous end of a capillary?

Answer 22

osmotic pressure [caused by blood protein albumin] pulls fluid back into the capillaries

Question 23

what are the three components of blood?

Answer 23

~55% of blood is plasma
~45% of blood is erythrocytes [RBCs]
~<1% of blood is leukocytes / platelets