Lecture 16-17 Flashcards
What is the function of arteries?
Transport of oxygenated blood
What is the function of arterioles?
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
What are the layers of arteries?
Tunica interna (intima) Tunica media Tunica externa
What are the 3 components of the tunica interna (intima)?
Endothelium
Basement membrane
Internal elastic lamina
Dennis, T or F? Tunica interna of the veins contains lining of simple squamous epithelium (endothelium), basement membrane, and layer of elastic tissue (internal elastic lamina).
False, Tunica interna of the arteries, not veins.
The ____ _____ is the thickest middle layer of the arteries that consists of elastic fibers and smooth muscle that extend circularly around the lumen.
Tunica media
Which layer of the arteries consists mainly of elastic and collagen fibers?
Tunica externa
T or F? In muscular arteries, an external elastic lamina composed of elastic tissue separates the tunica externa form the tunica media
True
Which type of arteries are capable of greater vasoconstriction and vasodilation to adjust blood flow.
Muscular
T or F? The aorta is a muscular artery with the largest diameter.
False, it is an elastic artery
The _____ innervates the smooth muscle in the tunica media.
SNS (Making the muscular arteries capable of greater vasoconstriction and vasodialation to adjust blood flow.
T or F? Normally, Endothelium is the only tissue that contacts blood.
True
T or F? Capillaries contain smooth muscle so they can perform vasoconstriction and vasodilation.
False, they DO NOT contain smooth muscle, so they CANNOT perform vasoconstriction or vasodilation.
T or F? Veins consist of the same 3 tunics as arteries but with more elastic tissue and smooth muscle than arteries.
False, less elastic tissue and smooth muscle
Veins are much more ________ than arteries which allows them to hold more blood and act as a reservoir.
compliant
_____ contains valves to prevent backflow of blood.
Veins
How is Cardiac Output (CO/Q) calculated?
CO = MAP / TPR CO = HR x SV
Blood flows through the body due to a ____ _____.
Pressure gradient
What is normal mean artery pressure?
Mean (MAP) = DBP + 1/3(SBP-DBP) = 93 mmHg
Diastolic = 80 mmHg
Systolic = 120 mmHg
How is Mean Arterial Pressure calculated (MAP)?
MAP = CO x TPR MAP = DBP + 1/3(SBP-DBP)
T or F? MAP represents the average arterial pressure during a single cardiac cycle.
True (average 93 mmHg [aorta])
_______ also represents the pressure gradient in the systemic circulation since the pressure in the right atrium is nearly 0 mmHg.
MAP
What is the mean pressure of the capillaries?
17 mmHg (mean)
What is the pressure gradient of veins and the right atrium?
0 mmHg
What is the major driving force blood flow through the systemic circulation?
MAP which represents the pressure gradient.