Quiz 2

Question 1

Which vascular bed has the highest cross-sectional area?

Answer 1

Capillaries

Question 2

What determines blood distribution to tissues?

Answer 2

Oxygen demand

Question 3

In which vessels does control of blood flow mainly occur

Answer 3

Arterioles

Question 4

The hearts of all species are able to maintain complete separation between oxygenated and deoxygenated blood?

Answer 4

False

Question 5

What happens to resistance in a blood vessel as radius of the vessel increases?

Answer 5

Decreases

Question 6

You have the following information on a patient: systolic arterial blood pressure = 120 mm Hg, diastolic arterial blood pressure = 75 mm Hg, and heart rate = 85 BPM. What is the mean atrial pressure?

Answer 6

75 mm Hg + 1/3 (systolic BP - diastolic BP)
75 mm Hg + 1/3 ( 120 m Hg - 75 mm Hg) = 90 mm Hg

Question 7

You have the following information on a dog
- end diastolic volume = 35 mL
- end systolic volume = 19 mL
- HR = 70 BPM
What is cardiac output?

Answer 7

(End-diastolic - end-systolic) HR = X
(35 mL - 19mL) X 70 BPM = 1210 mL/min

Question 8

A 440 kg horse has an end-diastolic volume of 740 mL and a stroke volume of 520 mL. What is the equation fraction?

Answer 8

Stroke volume / end-diastolic volume = X
520 mL / 740 mL = 0.70 X 100 = 70%

Question 9

A 20 kg lab has an
- end-diastolic volume = 45 mL
- end-systolic volume = 12
- heart rate = 90 BPM
what is stroke volume?

Answer 9

End-diastolic volume - end systolic volume = X
45 mL - 12 mL = 33 mL

Question 10

For most species, aortic pressure averages _________ and right atrial pressure averages ________

Answer 10

80-120 mm Hg
0-5 mm Hg

Question 11

Which ion is responsible for the upstroke in phase 0, of a cardiac action potential?

Answer 11

Sodium

Question 12

Which receptors are used by the sympathetic nervous system to increase heart rate, conduction velocity, and contractality?

Answer 12

Beta 1 receptors

Question 13

As heart rate increases, intracellular Ca concentration increases due to more Ca entering cell and more AP per unit time T/F

Answer 13

True

Question 14

Besides an increase in pressure, what else occurs during isovolumetric contraction of the left ventricle?

Answer 14

Valves are closed = volume remains constant

Question 15

When the left ventricle contracts and the mitral valve closes, this coincides with

Answer 15

The first heart sound

Question 16

What portion of the ECG represents depolarization of the atria

Answer 16

P wave

Question 17

What is the function of baroreceptors located in the walls of the carotid sinus and aortic arch

Answer 17

Responds quickly to keep atrial pressure constant

Question 18

During the effective refractory period, a stimulus may locally excite the tissue, but conduction of an action potential can’t occur - some Na+ channels are starting to open during this period

Answer 18

True

Question 19

Which type of blood vessel holds the unstressed volume

Answer 19

Veins

Question 20

What is the primary force causing fluid movement (filtration) out of the capillaries?

Answer 20

Capillary hydrostatic pressure

Question 21

Which circulation utilizes local metabolic control as the most important control mechanism

Answer 21

Coronary
Cerebral
Pulmonary

Question 22

If tension of the ventricle wall decreases, myocardial oxygen consumption increases

Answer 22

False

Question 23

Based on radius, which vessel would have the greatest resistance

Answer 23

Capillaries

Question 24

Which factor would be most likely to cause fluid to move out of the capillaries and into the tissues

Answer 24

High interstitial oncotic pressure

Question 25

What is the heart rate if the RR interval is 325 sec

Answer 25

185 bpm

Question 26

If a substance has a negative ionotropic effect on a heart, what happens to contractility?

Answer 26

Decreases