Arteries, Arterioles and Distribution Of Bloof Flow.

Question 0

Tunica intima.

Answer 0

No smooth muscle, elastic tissue.

Tight junctions. important role in the diameter of blood vessel by releasing factors.

Question 1

What are the three basic layers of a blood vessel?

Answer 1

Tunica intima, Tunica media and Tunica adventitia.

Question 2

Tunica media.

Answer 2

Circular smooth muscle and elastic tissue.
Smooth muscle innervated by sympathetic nervous system.
Elastic layer.

Question 3

Tunica adventitia.

Answer 3

Loosely woven connective tissue. Blood vessels, vasa vasorum and protection of these blood vessels.

Question 4

Which tissue present in an artery are not found in an ateriole?

Answer 4

Elastic and fibrous.

Question 5

Layers in an artery and arteriole.

Answer 5

Review the organization.

Question 6

Explain the rise in blood pressure with age.

Answer 6

Arteries stiffen with age, undergo atherosclerosis which leads to a rise in blood pressure.

Question 7

The pressure in an elastic tube will depend on?

Answer 7

The volume of the fluid,

The distensibility of the walls of the tube.

Question 8

Blood flow is directly proportional to?

Answer 8

Pressure difference and viscosity.

Question 9

How to calculate Pulse pressure?

Answer 9

Systolic - Diastolic pressure.

Question 10

How do you calculate mean arterial pressure?

Answer 10

Diastolic pressure + 1/3 pulse pressure.

Question 11

Pulse pressure on the graph.

Answer 11

Between highest and lowest points.

Question 12

What is pulse pressure used to indicate clinically?

Answer 12

Different heart valvular conditions. Aortic stenosis, aortic regurgitation.

Question 13

What might an impalpable pulse suggest?

Answer 13

Cardiac arrest, Hypovolemia, Peripheral arterial disease (intermittent claudiaction).

Question 14

Pressure in which arteries are very similar?

Answer 14

Carotid, renal and radial arteries.

Question 15

Identify sites for the palpation of pulses.

Answer 15

Carotid, brachial, radial, abdominal, femoral, popliteal, anterior amd posterior tibialis and dorsalis pedis pulse.

Question 16

What changes occur to blood flow from arteries to arterioles?

Answer 16

Decrease in pressure and pulsative to non pulsative.

Question 17

Cardiac output at rest?

Answer 17

5 L/min.

Question 18

Cardiac output during exercise?

Answer 18

12.5 L/min.

Question 19

Equation for flow?

Answer 19

Difference in pressure over Resistance.

Question 20

Equation for Resistance?

Answer 20

1/Radius to the power 4.

Question 21

Resistance and flow are both dependant on?

Answer 21

The radius of the blood vessel in question.

Question 22

Blood viscosity.

Answer 22

Is the measure of internal friction in blood or plasma.

Question 23

What determines the viscosity of blood?

Answer 23

Packed cell volume or hematocrit.

Question 24

Polycythemia.

Answer 24

Increase in RBC in response to hypoxia. May cause decrease in perfusion resulting in for e.g. bowel infarction and Raynaud’s phenomenon.

Question 25

Smooth muscle in arterioles maintain tone which is controlled.

Answer 25

Note.

Question 26

What are the local and reflex mechanisms for the control of arteriole diameter.

Answer 26

Local - Chemical (oxygen, carbon dioxide, adenosine, other stuff like endothelium factors - NO, local hormones - histamines, prostaglandins), physical and endothelium.
Reflex - Sympathetic (alpha receptors) and Hormonal (alpha and beta receptors).