L15 Circulation- Systemic Circulation I Flashcards
Define pulse pressure.
Systolic- diastolic
Explain how elastin functions as a structural component of the vascular wall.
Arteries have internal and external elastic lamina, which distinguishes it from veins
-Elastic lamina is very elastic, gives arteries compliance
Explain how smooth muscle functions as a structural component of the vascular wall.
Arteries- very thick and powerful, found in tunica media
Veins- not as strong
Explain how collagen functions as a structural component of the vascular wall.
Arteries- less, found in tunia adventitia
Veins- lots of connective tissue, well developed system
Define compliance.
1
Explain how vessel wall compliance affects arterial pressure.
Increasing V of blood, increases pressure, which decreases compliance
Explain windkessel (hydraulic filtering) properties of the aorta.
1
Define the relationship between velocity, flow and vessel cross sectional area.
1
Define the functional importance of wall/lumen diameter ratio to regulation of arterial pressure.
Higher wall thickness/lumen diameter = greater control of vessel diameter and blood flow
Define pressure pulse.
1
Define mean arterial pressure.
Diastolic pressure + 1/3 pulse pressure
What happens to pulse pressure as vessels get further from the heart?
Pulse pressure widens (systolic P increases and diastolic P decreases)
Do mean arterial pressure incline or decline throughout the circulatory system?
Continuously declines
What is the primary factor in determining mean arterial pressure?
Diastolic pressure
What is the pulse pressure in capillaries and veins?
No pulse pressure b/c of all the organs being diffused
Where is the greatest decrease in arterial pressure?
Across the arterioles
What are the compliance properties of elastic lamina, smooth muscle and collagen?
Elastic lamina has highest compliance, then smooth muscle, and collagen has lowest compliance
What are the structural features of continuous capillaries?
- Continuous endothelial cells
- No fenestrations in wall
- Tight jxns between cells
- Continuous basal lamina
- Found in muscle, connective tissue
What are the structural features of fenestrated capillaries?
- Continuous endothelial cells
- Fenestrations w/ and w/o diaphragms
- Continuous basal lamina
- Found in kidney and intestine
What are the structural features of discontinuous (sinusoidal) capillaries?
- Discontinuous endothelial cells separated by wide spaces
- Discontinuous basal lamina
- Found in liver, bone marrow, spleen
