CVS Flashcards
Functions of cvs?
Circulates, transports nutrients and oxygen, hormones and blood cells around the body.
Fights disease, stabilize temp, Ph & helps maintain homeostasis
What are the 3 essential components of the human cvs system?
Heart, blood and blood vessels
What is meant by having a “closed circulation?”
Blood never leaves the network of arteries, veins and capillaries
How much blood does an avergae human have? How much is rbc? Plasma?
5L
Rbc» 2L
Plasma» 3L
Where does most of our blood lie?
Peripheral veins (65%)
Where does the least of our blood lie?
In capillaries, but they have the bigest surface area which is needed for substance exchange!
How lomg can a patient live with a artificial heart inserted?
4 yrs approx
The heart has 2 major arteries…what r they?
Left and right coronory system
Define an “end artery” & give examples
A terminal artery supplying all or most of the blood to a body part without collateral circulation.
What are 2 types of end arteries?
Give examples for each
1) Absolute (true) end artery: there are no anastomoses, IN THE RETINA
2) Functional end arteries: have anastomoses
Ex coronory arteries, splenic artery, cerebral artery, renal artery
During a stenosis, what special action do arteries have to compensate this?
They form a collateral circulation, but it takes ages tho.
What is a collateral circulation?
the alternate circulation around a blocked artery or vein via nearby minor vessels. branches formed between adjacent blood vessels.
The left and right coronory artery arise from what?
The aorta
What is an example lf a natural collateral circulation in the body?
When the radial and ulnar arteries take the job of the brachial artery if damaged
List the component sof the electrical conducting system of the heart in order
Sa node Av node Bundle of his Left and r bundle branch Purkunjee fibers
Why is the AV node implise delayed for 0.1 sec?
To allow the atria to respond and complete it’s contraction so the ventricles cam contract