Focus 8

Question 1

Three types of reconditioning organs

Answer 1

– Digestive organs
– Kidneys
– Skin

Question 2

Blood volume moving over time. Directly proportional to pressure gradient

Answer 2

Blood flow (F)

Question 3

Difference in pressure between two ends of vessel. Determines flowrate

Answer 3

Pressure

Question 4

Measure of the opposition to flow. Friction

Answer 4

Resistance (R)

Question 5

Resistance depends on (3)

Answer 5

– Blood viscosity
– Vessel length
– Vessel radius (most important)

Question 6

Elastic pressure reservoir

Answer 6

Arteries

Question 7

Resistance vessels

Answer 7

Arterioles

Question 8

Increase surface area. Thin walls exchange materials

Answer 8

Capillaries

Question 9

Drains capillary beds

Answer 9

Venules

Question 10

Blood reservoir. Stretch but no recoil

Answer 10

Veins

Question 11

Altered to match blood flow to tissue demands

Answer 11

Radius and thus resistance

Question 12

Partial constriction in arterioles (can override to change flow)

Answer 12

Sympathetic tone

Question 13

Intrinsic factors causing change in radius

Answer 13

Metabolic*

Heat/cold

Question 14

Extrinsic factors causing change in radius

Answer 14

– Sympathetic

– hormones

Question 15

Vasodilation intrinsic controls

Answer 15

v O2
^ CO2
^ H+ (v pH)
^ temperature

Question 16

Vasoconstriction intrinsic controls

Answer 16

^ O2
v CO2
v H+ (^ pH)
v temperature

Question 17

Helps keep blood flow constant despite wide variations in mean arterial pressure.

Answer 17

Myogenic factors

^ vessel stretch-> constriction

Question 18

Endothelial cells release in response to metabolic or myogenic factors

Answer 18

Paracrine chemicals

Question 19

Types of paracrine chemicals (2)

Answer 19

– Endothelin (vasocon)
– Nitric oxide (vasodi)
– Histamine (vasodi)

Question 20

Organs that receive larger bloodflow than needed and tolerate temporary reductions

Answer 20

Reconditioning organs

Question 21

Vasopressin hormone

Answer 21

Increases water retention decrease his urine. Vasoconstrictor

Question 22

Angiotensin hormone

Answer 22

Vasoconstrictor

Question 23

Aldosterone hormone

Answer 23

Sodium and water retention, decrease urine. Vasoconstrictor

Question 24

Tends to push fluids out of capillaries into interstitial fluid

Answer 24

Capillary blood pressure

Question 25

Tends to pull fluids into capillaries from interstitial fluid

Answer 25

Plasma osmotic pressure

Question 26

Helps balance ECF normally more fluid is filtered than reabsorbed

Answer 26

Bulk flow

Question 27

What increases venous return (5)

Answer 27

``` – Sympathetic vasoconstriction - muscle pump – Penis valves – Respiratory pop – Heart ```

Question 28

Where are Baroreceptors located

Answer 28

Aortic arch and carotid sinus