Overview of Function of CVS Flashcards
What is the function of the CVS?
Is to supply the brain with oxygen
What is the role of bulk flow system?
02 and CO2 exchange
Carries nutrients, metabolites, hormones and heat
How is the CVS flexible?
Pump can vary output
Vessels can redirect blood
Vessels can store blood
What is left side of heart responsible for?
Systemic circulation
What is the right side of the heart responsible for?
Pulmonary circulation
What is the reason for blood pumping in a series?
Output must be equal so does not cause accumulation
What does the vascular beds lying in parallel mean?
All tissues get oxygenated blood
Allows regional redirection of blood
What is the only exception to vascular beds lying in a parallel?
Gut and liver lie in a series due to liver having a portal system
What organs have more oxygen consumption compare to cardiac output?
Heart
Skin - thermoregulation
Kidneys - filtration
What is the pressure difference equal to?
Mean arterial pressure - central venous pressure
This affects all tissues
What side of the heart gives mean arterial pressure?
Left side
What side of the heart gives central venous pressure?
Right side
Explain Darcy’s law
Flow = difference in pressure/ resistance
What is resistance affected by?
Controlled by radius to power of 4
This selectively redirects flow
Describe arterioles acting like taps
They control resistance and therefore flow to each vascular bed
Explain fractional distribution
Proportion of blood in these veins and venules compared to rest of systemic circulation
Why are veins and venules described as capacitance vessels?
They have the ability to store blood
Describe the structure and function of the aorta
Elastic arteries
Wide lumen - low resistance
Thick elastic wall
Damp pressure variations
Describe structure and function of arteries
Muscular arteries
Wide lumen - low resistance to blood flow
Strong, thick, non-elastic wall
Low resistance conduit
Describe the structure and function of arterioles
Resistance vessels
Narrow lumen
Thick contractile wall - Control resistance and flow, and allow regional redirection of blood
Explain the structure and function of capillaries
Exchange vessels
Narrow lumen
Thin wall
Explain the structure and function of blood vessels
Capacitance vessels
Wide lumen
Thin, distensible wall
Low resistance conduit and reservoir
Fractional distribution
What is the function of the septum in the heart?
Separates left and right sides
What is the myocardium?
The muscular tissue of the heart
What are the valves of the heart?
Aortic, pulmonary, mitral and tricuspid valves
Explain the papillary muscle and chordae tendinea?
Papillary muscle contracts with ventricles and maintains tension on chordae tendinea
This prevents blood from inverting
Where are the valves loacted?
Aortic and pulmonary valve are at anterior of heat and have 3 flaps
Tricuspid and mitral valve are posterior of heart
Mitral has only 2 flaps
Explain the vena cava
Superior and inferior vena cava bring deoxygenated blood into right atrium
Explain function of pulmonary artery
Carries deoxygenated blood from right side of heart to lungs
Explain the role of the aorta
Originates from left ventricle of heart
Takes oxygenated blood to tissues
Explain the role of the pulmonary vein
Transfer oxygenated blood from the lungs to the left atrium of heart
What is the function of the pulmonary trunk?
Transmit deoxygenated blood from right ventricle to lung
Trunk splits into left and right arteries
