Function of CVS Flashcards
Define the function of the cardiovascular system.
The function of the heart is to supply the brain with oxygen
Transport of of oxygen and carbon dioxide, nutrients, metabolites, hormones and thermoregulation.
Justify the significance of pressure, resistance and capacitance with respect to the cardiovascular system.
what are elastic arteries
elastic arteries are located nearer the heart and maintain a relatively constant pressure gradient despite the constant pumping action of the heart.
how is the heart flexible
pump can vary output, vessels can redirect blood, vessels can store blood
are the left and right pump in series or parallel
pumps are in series therefore output must be equal.
are vascular beds parallel or series
parallel so all tissues get oxygenated blood and allows regional redirection of blood during activities such as running
are gut and liver in series or parallel
series
define darcys laws
flow= change in pressure/resistance
resistance is controlled by radius of vessel to the power 4
what is the fractional distribution of blood
Proportion of blood in veins and venues versus the rest of the systemic circulation
what are muscular arteries
wide lumen, strong thick elastic wall and distribute blood to various parts of the body
what are arterioles
arterioles have a narrow lumen, thick contractile wall and are resistance vessels and can change diameter depending how much blood is flowing through. Allow regional redirection of blood. Act like taps
what are veins
veins are capacitance vessels and have the ability to store blood
what are venules
capacitance vessels, wide lumen, thin wall, low resistance and allow fractional distribution of blood between veins and rest of circulation
what are capillaries
one layer of endothelial cells thick, have a large surface to volume ratio and allows oxygen to diffuse from the blood to the tissues
