Cardiovascular system: Blood circuits 1/2 Flashcards
Label the diagram
What are the relative pressures and resistances of the systemic and pulmonary circuits?
Systemic = high pressure + resistance
Pulmonary = medium pressure + resistance
What is the pressure higher in the systemic circuit than the pulmonary circuit?
The systemic circuit is much larger than the pulmonary circuit which means there is a lot more resistance. This requires a lot more pressure in order to pump blood around the body
What ventricles pressurises the pulmonary and systemic circuits?
Pulmonary is pressurised/pumped by the right ventricle
Systemic is pressurised/pumped by the left ventricle
Why does the liver have two supplies of blood?
One supply of blood comes from the gut which contains the absorbed nutrients, however this is deoxygenated so it has another oxygenated supply
What is a vein that is not connected to the heart called?
Hepatic portal vein
What does the pulmonary and systemic circuit provide blood to?
Pulmonary: Supplies blood to the lungs (to be deoxygenated FYI)
Systemic: Supplies blood to the body
What percent of blood is in the pulmonary, systemic circuit and heart?
9% || 84% || 7%
What is the total amount of blood in the body? How much blood is pumped around the body per minute? per day?
5L
5Lmin-1 and 7,000 Lday-1
During exercise, how much can the blood output of the hear be?
4-8 times greater (the greater the increase the greater the fitness FYI)
Label the diagram
What are the three improvements in the diagram (don’t explain them, just what they are)?
1 - An atrium
How does an atrium improve the hearts ability to pump?
The expanding of the heart is passive (as the contracting is active) so by having an atrium that allows more blood to get into the heart passively and having it more accessible/faster drainage during contraction increases the efficiency of the pump
How does moving the inlet and outlet to the same side of the heart improve the hearts ability to pump?
It allows a third wall to be able to contribute to the contraction of the heart so more power can be generated and the other two walls can be smaller
How does an auricle improve the hearts ability to pump
Increasing the size of the atrium allows more blood to get into the heart/get pumped
Label the diagram, What view of the heart is this?
Anterior view
What are the pressures of the ventricles?
Right = 27mmHg
Left = 120mmHg
What are the pressures of the atriums?
Right = 5mmHg
Left = 8mmHg
Why are the vena cava’s pointing up and down but the pulmonary arteries pointing to the side?
Vena cava’s are draining blood from above and below the heart therefore veins above and below. Pulmonary arteries are delivering blood the lungs which are on either side of the heart.
Label the diagram. What is the view of this heart?
Posterior view
Label the diagram
What are the two valves in the heart called and where are they? What are they called together?
Tricuspid valve in the right atrium/ventricle border, Bicuspid/Mitral valve in the left atrium/ventricle border
Atrioventricular (AV) valves
What are the AV vales made of?
Fibrous connective tissue
What is connected to the AV valves to stop them from flipping upwards?
Chordae tendineae (Tendinous cords)
What is the purpose of Chordae tendineae?
Stops the valves and therefore prevent blood from betting forced into the atrium during contraction
What controls the force applied to the Chordae tendineae? What is their purpose?
Papillary muscles
Tense as the valves are pushed back preventing the tendons to be too long therefore blood leaks back into atrium
Are the AV valves relatively large or small? Why?
They are quite large
This is because the inlets are large
At birth what is the relative size of the ventricles? Why does it change as you get older?
They are the same size
As you get older the systemic circuit requires much more pumping force than the pulmonary circuit so the left ventricle grows more
What are the peak pressures in the left and right ventricle?
Left = 120mmHg
Right = 27mmHg
What are the relative wall thicknesses of the ventricles?
Left:right, 3:1
What are the inlet and outlet valves called?
Inlet: Atrioventricular valves
Outlet: Semi-lunar valve
Where are the outlet valves in the heart?
At the base of the pulmonary trunk and aorta
Which of these valves is an outlet and inlet valve and what are their proper names?
1 is an inlet/Atrioventricular valve
What is the relative size of outlet valves compared to inlet valves? Why?
They are smaller
There is a smaller diameter in the arteries as blood is being transported at a higher pressure
