1. Human Physiology Unit Seven Objective Twelve

2. Blood Volume and Its Control
Blood volume is the amount of extracellular water found in the blood
Increasing blood volume would increase EDV and therefore stroke volume
Decreasing blood volume would decrease EDV and therefore stroke volume

3. Blood Volume and Its Control
Blood volume can be regulated by ADH and aldosterone
ADH (antidiuretic hormone) promotes thirst and the retention of water

4. Blood Volume and Its Control Increased blood volume
Adrenal cortex 
Aldosterone
salt retention
(water retention)
Increased blood volume
Aldosterone promotes salt retention, which will lead to water retention

5. Human Physiology Unit Seven Objective Thirteen

6. Definitions
Blood pressure - the pressure exerted on the vessels of the circulatory system
Systolic pressure - pressure exerted on the arteries during systole
Diastolic pressure - pressure exerted on the arteries during diastole
Pulse pressure - systolic pressure minus the diastolic pressure

7. Definitions
Mean arterial pressure - the diastolic pressure plus one third the pulse pressure
Blood pressure decreases as blood moves farther away from the heart. Therefore arteries are under the highest pressures, while capillaries and veins are under little or no pressure

8. Human Physiology Unit Seven Objective Fourteen

9. Poiseuille’s Law Pr4() L(8) Blood flow =
Vessel length and blood viscosity do not change significantly, therefore the most important variable in changing blood flow is vessel radius

10. Human Physiology Unit Seven Objective Fifteen

11. Fluid Exchange Between Capillaries and Tissues

12. Human Physiology Unit Seven Objective Sixteen

13. Edema
The excessive accumulation of fluid in the interstitial spaces of the tissues
This condition can be temporary or chronic, depending upon its cause

14. Edema Five causes of edema - * Hypertension * Plasma colloid leakage
* Myxedema
* Decrease in plasma proteins
* Obstruction of lymphatic
vessels

15. Human Physiology Unit Seven Objective Seventeen

16. Blood Pressure Regulation Through Resistance Changes
Angiotensin II - compound produced in the blood during times of low blood volume or pressure
This is an example of extrinsic control

17. Blood Pressure Regulation Through Resistance Changes
Sympathetic innervation - causes vasoconstriction and increases cardiac output
Parasympathetic innervation - causes limited vasodilation and decreases cardiac output
These are examples of extrinsic control

18. Blood Pressure Regulation Through Resistance Changes
Myogenic action - direct responses of vascular smooth muscle in response to changes in pressure
Metabolic changes - decreases in oxygen or pH, and increases in carbon dioxide lead to localized vasodilation
These are examples of intrinsic control

19. Human Physiology Unit Seven Objective Eighteen

20. The Baroreceptor Reflex
Integrating
Center
Sensor
Effectors
Stimulus
Response

21. The Baroreceptor Reflex

22. Human Physiology Unit Seven Objectives Nineteen through Twenty Two

23. Not Finished!