1. Capillary Exchange Diffusion Transcytosis Bulk Flow
Most important solute exchange method
O2, CO2, glucose, a.a., hormones = [ ] gradients
Plasma solutes cross capillary walls
Blood-brain barrier = exception
Transcytosis
Enclosing substances in tiny vesicles.
Endocytosis into cells.
Bulk Flow
Important regulation of relative volumes of blood and interstitial fluid
Filtration
Reabsorption

2. Capillary Exchange
Blood hydrostatic pressure pushes fluid out of capillaries (filtration).
Blood colloid osmotic pressure pulls fluid into the capillaries (reabsorption).

3. Figure 21.7 Capillary exchange
Spend close to a full class going over this diagram. Use the written notes!
Figure 21.7 Capillary exchange

4. Hemodynamics Factors affecting BF 4 main factors
SV, HR, Pressure, Resistance

5. Blood Flow
Volume of blood flowing through any tissue in a given time period.
BF = BV mL/min
Total blood flow = cardiac output
BF= CO; (SV X HR)
The same factors that change CO change BF
Stroke volume: preload and contractility
Heart rate: nervous system and chemicals

6. Blood Flow Distribution of CO to tissues depends on:
Pressure difference
Vascular resistance
4 factors affecting BF
Ultimately controlled by contractility (large role) and endocrine system NE and E (lesser role)

7. Blood Pressure
Pressure exerted by blood on the wall of an artery during ventricular systole and diastole.
Pulse pressure
Difference between systolic and diastolic pressures
Mean arterial pressure
The average BP in arteries

8. Blood Pressure BP CO , VR , BV (HR,SV) Blood itself has a role in BP
More blood = é BP
Less blood = ê BP
Blood doping
Dehydration
Injury BV

9. Blood Pressure BP (MAP) = CO x R BP depends on total BV in system
If resistance remains steady
é CO = é BP
ê CO = ê BP
BP depends on total BV in system
é BV = é BP
ê BV = ê BP

10. Vascular Resistance
Opposition to flow due to friction between blood & vessel walls
3 factors:
Diameter of blood vessels
Blood viscosity
Total blood vessel length

11. Vascular Resistance Diameter of blood vessels Blood Viscosity
Total blood vessel length
Resistance is inversely proportional to the 4th power of the radius of the blood vessel
R  1/ r4
The smaller the radius of the vessel = the greater the resistance it offers to BF
Resistance is directly proportional to viscosity
The greater the viscosity, the greater the resistance
Pathology
Hematocrit
Resistance is directly proportional to blood vessel length
Longer the vessel, greater resistance to blood that flows through it.

12. Systemic Vascular Resistance
Total peripheral resistance
All vascular resistances offered by systemic blood vessels
Most in arterioles, capillaries, venules
** Arterioles

13. Figure 21.9 Venous Return
Pressure gradient (contractions of L.V.) between venules and R.A.
Valves
Skeletal Muscle Pump*
Respiratory Pump*

14. Figure 21.10

15. Figure 21.11

16. Blood Vessel Topics Components of the blood vessel system
Basic structures of blood vessels
Blood distribution
Capillary exchange
Factors affecting blood pressure and flow
Control of blood pressure and flow
Circulatory routes

17. Figure 21.12

18. Figure 21.13

19. Blood Vessel
Topics
Circulatory
Routes – in lab
Figure 21.17
21_17

20. Figure 21.18a
21_18a

21. 21_18b
21_18b

22. 21_19abc
21_19abc

23. 21_19d
21_19d

24. 21_20
21_20

25. 21_21a
21_21a

26. 21_21b
21_21b

27. 21_21c
21_21c

28. 21_21d
21_21d

29. 21_22
21_22

30. 21_23
21_23

31. 21_24
21_24

32. 21_25abcd
21_25abc

33. 21_26a
21_26a

34. 21_26b
21_26b

35. 21_27
21_27

36. 21_28a
21_28a

37. 21_28b
21_28b

38. 21_29
21_29

39. 21_30ab
21_30ab

40. 21_30c
21_30c

41. 21_31
21_31

42. 21_EX02
21_EX02

43. 21_EX03
21_EX03

44. 21_EX04
21_EX04

45. 21_EX05
21_EX05

46. 21_EX06
21_EX06

47. 21_EX08
21_EX08

48. 21_EX09
21_EX09

49. 21_EX10
21_EX10

50. 21_EX11
21_EX11

51. 21_EX12
21_EX12

52. 21_FOH
21_FOH