functional model of the cardiovascular system figure 15-1
TRANSCRIPT
Figure 15-3
MIcrocirculation
Capillaries lack smooth muscle and elastic tissue reinforcement which facilitates exchange
Figure 15-4a, step 1
Elastic Recoil in Arteries(a) Ventricular contraction
Ventricle contracts.
Arterioles
1
1
Figure 15-4a, steps 1–2
Elastic Recoil in Arteries(a) Ventricular contraction
Ventricle contracts. Semilunar valve opens.
Arterioles
1
1 2
2
Figure 15-4a, steps 1–3
Elastic Recoil in Arteries(a) Ventricular contraction
Ventricle contracts.
Aorta and arteries expand and store pressure in elastic walls.
Semilunar valve opens.
Arterioles
1
1 2
2
3
3
Figure 15-4b, step 1
Elastic Recoil in Arteries(b) Ventricular relaxation
Isovolumic ventricularrelaxation occurs.
1
1
Figure 15-4b, steps 1–2
Elastic Recoil in Arteries(b) Ventricular relaxation
Isovolumic ventricularrelaxation occurs.
Semilunar valve shuts, preventing flow back into ventricle.
1
2
21
Figure 15-4b, steps 1–3
Elastic Recoil in Arteries(b) Ventricular relaxation
Isovolumic ventricularrelaxation occurs.
Elastic recoil of arteries sends blood forward into rest of circulatory system.
Semilunar valve shuts, preventing flow back into ventricle.
1
2
3
3
21
Figure 15-5
Pressure throughout the Systemic Circulation
Blood pressure is highest in the arteries and decreases continuously as it flows through the circulatory system
Blood Pressure
Pulse Pressure = systolic P – diastolic P
Valves ensure one-way flow in veins
MAP = diastolic P + 1/3(systolic P – diastolic P)
Figure 15-8
Blood Pressure
Mean arterial pressure is a function of cardiac output and resistance in the arterioles
Figure 15-9
Blood Pressure
Blood pressure control involves both the cardiovascular system and the renal system
Arteriolar Resistance
Myogenic autoregulation
Paracrines Active hyperemia
Sympathetic control SNS: norepinephrine
Adrenal medulla: epinephrine
Figure 15-14a
Blood Flow
Blood flow through individual blood vessels is determined by vessel’s resistance to flow
Figure 15-14b
Blood Flow
Blood flow through individual blood vessels is determined by vessel’s resistance to flow
Flow 1/resistance
Figure 15-18a
Fluid Exchange at a Capillary
Hydrostatic pressure and osmotic pressure regulate bulk flow
Animation: Cardiovascular System: Autoregulation and Capillary DynamicsPLAY
Figure 15-21
Medullary cardiovascular
control center
Carotid and aorticbaroreceptors
Change in blood
pressure
Parasympatheticneurons
Sympatheticneurons
Veins
Arterioles
Ventricles
SA node
Integrating center
Stimulus
Efferent pathway
Effector
Sensor/receptor
KEY
Blood Pressure
Components of the baroreceptor reflex
Figure 15-25
Hypertension
The relationship between blood pressure and the risk of developing cardiovascular disease
Essential hypertension has no clear cause other than hereditary