3.8 -- Blood Flow Regulation

Question 1

Does blood flow up or down a pressure gradient?

Answer 1

Down a pressure gradient

Question 2

Mean blood pressure on the systemic circulation ranges from just under 100 mmHg in the what to a low of just a few mmHg in the venae cavae?

Answer 2

Aorta

Question 3

What drives blood flow?

Answer 3

Pressure differentials (Pressure Gradient: Change in P)

Question 4

What opposes blood flow?

Answer 4

Resistance

Question 5

Pressure created by contracting ventricles is transferred to what?

Answer 5

Blood

Question 6

Driving pressure is created by the what?

Answer 6

Ventricles

Question 7

If blood vessels dilate, blood pressure does what?

Answer 7

Decreases

Question 8

If blood vessels constrict, blood pressure what?

Answer 8

Increases

Question 9

Volume changes affect what in the cardiovascular system?

Answer 9

Blood pressure

Question 10

Flow through a tube is directly what to the pressure gradient?

Answer 10

Directly proportional

Question 11

The higher the pressure gradient, the greater the what?

Answer 11

Fluid flow

Question 12

Flow is determined by the difference in what, not absolute what?

Answer 12

Pressure x2

Question 13

Fluid only flows if there is what sort of pressure gradient?

Answer 13

A positive pressure gradient

Question 14

Flow through a tube is what to resistance?

Answer 14

Inversely proportional

Question 15

If resistance increases, flow does what? What does this mean for pressure gradient?

Answer 15

Decreases, with a decrease in the pressure gradient too

Question 16

Resistance is what to viscosity, or thickness, of the fluid?

Answer 16

Proportional

Question 17

Resistance is what to length of the tube/blood vessel?

Answer 17

Proportional

Question 18

Resistance is what to tube radius to the 4th power?

Answer 18

Inversely proportional

Question 19

Smooth muscle constriction/dilation in the arteriole vessels change the what of vessels?

Answer 19

Radius of vessels

Question 20

A small change in radius has a large effect on what to blood flow?

Answer 20

Resistance

Question 21

Vasoconstriction is a decrease in blood vessel diameter/radius and decreases blood what?

Answer 21

Blood flow

Question 22

Vasodilation is an increase in blood vessel diameter/radius and increases blood what?

Answer 22

Blood flow

Question 23

Flow of blood in the cardiovascular system is what to the pressure gradient and what to the resistance?

Answer 23

Directly proportional to the pressure gradient and inversely proportional to the resistance

Question 24

Under normal conditions, the most important factor determining vascular resistance to flow is what?

Answer 24

Vessel diameter

Question 25

Arterioles have a lot of smooth muscle, making them a key regulator of what?

Answer 25

Resistance

Question 26

What is total peripheral resistance?

Answer 26

The sum of all vascular resistance in the systemic circulation

Question 27

Generalized vasoconstriction does what to TPR?

Answer 27

Increases TPR

Question 28

Generalized vasodilation does what to TPR?

Answer 28

Decreases TPR

Question 29

Blood flow in organs runs parallel to each other, so a change in vessel what within one organ does not directly affect another?

Answer 29

Vessel resistance

Question 30

Dilation in vessels of a large organ (Skeletal muscles) can do what to TPR and mean arterial pressure?

Answer 30

Decrease TPR and MAP

Question 31

Increased what and overall vasoconstriction can be balanced by vessel dilation to skeletal muscles during exercise?

Answer 31

Cardiac output

Question 32

During exercise, there is vasodilation to skeletal muscles and vasoconstriction everywhere else (rest/digest organs), so what does not greatly increase?

Answer 32

TPR

Question 33

Autonomic and endocrine control of blood flow is extrinsic or intrinsic regulation of blood flow?

Answer 33

Extrinsic regulation of blood flow

Question 34

Sympathetic nerves are adrenergic or cholinergic?

Answer 34

Adrenergic

Question 35

Increased TPR via release of what sympathetic hormone onto smooth muscles of arterioles in viscera and skin?

Answer 35

Norepinephrine

Question 36

The smooth muscles of arterioles in viscera and skin have what receptors that get vasoconstriction at those vessels?

Answer 36

Alpha 1 receptors

Question 37

Arterioles leading to skeletal muscles express what receptors? These leads to adrenal epinephrine binding causes relaxation/dilation of vessels to skeletal muscles to increase flow so what is lower here?

Answer 37

Beta 2 receptors, TPR

Question 38

Parasympathetic nerves are adrenergic or cholinergic?

Answer 38

Cholinergic

Question 39

What parasympathetic hormone leads to vasodilation?

Answer 39

Acetylcholine

Question 40

What is limited to the digestive tract, external genitalia, and salivary glands?

Answer 40

Parasympathetic nerves

Question 41

What is less important to controlling TPR due to limited influence?

Answer 41

Parasympathetic nerves

Question 42

Norepinephrine release to what receptors on arteriole smooth muscle?

Answer 42

Alpha 1 receptors

Question 43

Which of the following extrinsic agents has the effect of vasodilation? Alpha-adrenergic, beta-adrenergic, cholinergic, parasympathetic nerves, Angiotensin 2, and ADH (vasopressin)

Answer 43

Alpha-adrenergic, Angiotensin 2, and ADH (vasopressin)

Question 44

Which of the following extrinsic agents has the effect of vasoconstriction? Alpha-adrenergic, beta-adrenergic, cholinergic, parasympathetic nerves, Angiotensin 2, and ADH (vasopressin)

Answer 44

Beta-adrenergic, cholinergic, and parasympathetic nerves

Question 45

Which of the following extrinsic agents are neural? Alpha-adrenergic, beta-adrenergic, cholinergic, parasympathetic nerves, Angiotensin 2, and ADH (vasopressin)

Answer 45

Alpha-adrenergic, beta-adrenergic, cholinergic, and parasympathetic nerves

Question 46

Which of the following extrinsic agents are endocrine? Alpha-adrenergic, beta-adrenergic, cholinergic, parasympathetic nerves, Angiotensin 2, and ADH (vasopressin)

Answer 46

Angiotensin 2 and ADH (vasopressin)

Question 47

Matching blood flow to increased cell metabolism is extrinsic or intrinsic regulation of blood flow?

Answer 47

Intrinsic regulation

Question 48

Decreasing tissue pH, release of K+ and paracrine signals, and decreasing pressure in O2 and increasing pressure in CO2 due to increased cell metabolism are examples of what?

Answer 48

Metabolic control mechanisms

Question 49

If metabolism increases, what happens to resistance and blood flow?

Answer 49

Resistance decreases and blood flow increases