Functions of the Heart Flashcards
How are vascular beds formed so that blood is pumped and tissues are oxygenated equally ?
Most of the vascular bed are in parallel which allows them to be oxygenated equally and also allows for regional redirection of blood.
How do the left & right side of the heart pump ?
In series
What two part of the body have their own blood flow which does not mix with the systemic blood flow ?
The liver, gut, pituitary & hypothalamus.
How is the flow calculated ?
Flow = The difference in pressure/ Resistance
What is resistance controlled by ?
Radius of the vessel
What vascular structure acts as a tap controlling flow and resistance to each vascular bed ?
Aterioles
What are the defining features of the aorta and its wall ?
The aorta is an elastic artery, with a wide lumen & varied pressures.
What are the defining features of arteries (non-elastic) ?
Wide lumen, “muscular arteries” & thick walls
What are the defining features of arterioles ?
Bigger resistance & regulate blood pressure. They can vary the resistance of blood flow which allows regional directional blood flow.
What are the defining features of capillaries ?
These are exchange vessels with a narrow lumen and thin walls.
What are the defining features of veins/venules ?
Wide lumen with distensible wall. They have the capacity to store blood and release it when necessary & have less resistance.
Which side of the heart has a thicker more muscular wall ?
The left side as it has to pump blood to the systemic circulation.
Where in the heart is the Aortic valve found ?
Left ventricle (exit)
Where in the heart is the Pulmonary valve found ?
Right ventricle (exit)
Where in the heart is the Tricuspid valve found ?
Right atrium
