Lectures 16 & 17: Circulation Flashcards
(122 cards)
What type of vessel does gas exchange occur?
capillaries
Are arteries or veins more compliant? (compliant: referring to the ability to stretch out and not want to recoil and push back on the blood)
veins
Which vessel is the least compliant?
A: infused 200mL blood, pressure rose 20mmHg
B: infused 200mL blood, pressure rose 30mmHg
C: infused 100mL blood, pressure rose 30mmHg
Vessel C because you infused the least amount and pressure rose a greater amount
What will happen to blood flow through the body if blood pressure drops too low?
it will decrease
Which component of RAAS directly increases TPR?
Ang II
Which component of RAAS increases intravascular blood volume?
Ang II & Aldosterone
What receptors are responsible for increased HR?
Beta 1
What receptors are responsible for vasoconstriction and venoconstriction?
Alpha 1
What is the function of arteries?
transporting oxygenated blood
What is the function of arterioles?
they act as valves for entry into capillaries
What is the function of capillaries?
gas and nutrient exchange
What is the function of venules?
collects blood from capillary
What is the function of veins?
Carry deoxygenated blood back to the heart
The walls of arteries have three layers. The layers are also called what?
Tunics
What is the innermost layer of the wall of arteries called?
Tunica interna (intima)
What does the tunica interna contain?
lining of simple squamous epithelium (endothelium), basement membrane, and layer of elastic tissue (internal elastic lamina)
What does the endothelium (of the tunica interna) line?
the entire CV system
What is the only tissue (referring to the tunica interna) that contacts blood?
endothelium
What is the tunica media (arteries)?
the middle, thickest layer of the wall of arteries
What does the tunica media contain?
elastic fibers and smooth muscle that extend circularly around the lumen
What is the tunica externa?
the outermost layer of the wall of arteries
What is the tunica externa composed of?
Mainly of elastic and collagen fibers
In muscular arteries, what separates the tunica externa from the tunica media?
an external elastic lamina composed of elastic tissue
What are the two types of arteries?
elastic arteries and muscular arteries