Hemodynamics and Circulation Flashcards
Blood vessels have ________ (open/closed) circulation.
Closed
What are the major functions of the circulatory system?
- Transporting nutrients to the tissues
- Carrying oxygen from the lungs to the rest of the body
- Transporting waste products aray from the tissues
- Transporting hormones
- Distributing heat
What is the function of the aorta?
Transports blood to tissues under high pressure (100 mmHg)
What is the function of the superior and inferior vena cava?
- Returns blood to the heart under low pressure
- Serves as a reservoir of blood
What is the function of veins?
Conduit to the heart and reservoir
What is the function of the venules?
Blood collectors
What is the function of arteries?
To transport blood under high pressure
What is the function of arterioles?
Control conduits/gate keepers
Speed of blood flow in cm/sec is inversely related to ___________.
Cross sectional area
NOTE: Blood flow is slower in the arterial branches

Blood flow is the aorta is ______ cm/sec, while flow in capillaries is _____ cm/sec.
40;0.1
NOTE: Slow rate in capillaries allows for exchange
Circulation time is the time it takes a drop of blood to travel from ________ to ________.
Right atrium back to right atrium
Which component of the circulation has the largest total cross-sectional area? Which has the smallest?
Largest: Capillaries (2500 cm)
Smallest: Aorta (2.5 cm)
NOTE: CSA of capillaries is 1000 times higher than aorta
Rank the velocity of blood flow from component with the highest to component with the lowest.
Aorta> Arterioles> Small veins> Capilaries
*Velocity of blood flow= (Blood flow)/ (cross sectional area)
What are the units of the velocity of blood flow?
mm/sec
Largest pressure drop across the ___________ junction.
Arteriolar-capillary
Blood pressure is the highest in the ________.
Aorta
Blood pressure is defined as:
Pressure exerted by blood on walls of a vessel
*Caused by contraction of the ventricles
Pressure ___________ (falls/rises) steadily in systemic circulation with distance from left ventricle.
Falls
NOTE: BP is 35 mmHg entering the capillaries and 0 mmHg entering the right atrium
If decrease in blood volume is over _______%, BP drops.
10
Water rentention _________ (increases/decreases) blood pressure.
Increases
Compare the mean diameter of arteries and veins.
Mean diameter of veins (5 mm) is greater than the mean diameter of arteries (4mm).
NOTE: Arteries are thicker than veins
Korotkoff sounds
blood flowsounds that healthcare providers observe while taking blood pressure with a sphygmomanometer over the brachial artery in the antecubital fossa.
Korotkoff sounds are created by _______ blood flow through the compressed artery.
Pulsatile
NOTE: Blood flow is silent when the artery is no longer compressed
Pulse pressure
Systolic-Diastolic


