Cardiovascular system: Blood circuits 1/2

Question 1

Label the diagram

Answer 1

Question 2

What are the relative pressures and resistances of the systemic and pulmonary circuits?

Answer 2

Systemic = high pressure + resistance

Pulmonary = medium pressure + resistance

Question 3

What is the pressure higher in the systemic circuit than the pulmonary circuit?

Answer 3

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

Question 4

What ventricles pressurises the pulmonary and systemic circuits?

Answer 4

Pulmonary is pressurised/pumped by the right ventricle

Systemic is pressurised/pumped by the left ventricle

Question 5

Why does the liver have two supplies of blood?

Answer 5

One supply of blood comes from the gut which contains the absorbed nutrients, however this is deoxygenated so it has another oxygenated supply

Question 6

What is a vein that is not connected to the heart called?

Answer 6

Hepatic portal vein

Question 7

What does the pulmonary and systemic circuit provide blood to?

Answer 7

Pulmonary: Supplies blood to the lungs (to be deoxygenated FYI)

Systemic: Supplies blood to the body

Question 8

What percent of blood is in the pulmonary, systemic circuit and heart?

Answer 8

9% || 84% || 7%

Question 9

What is the total amount of blood in the body? How much blood is pumped around the body per minute? per day?

Answer 9

5L

5Lmin-1 and 7,000 Lday-1

Question 10

During exercise, how much can the blood output of the hear be?

Answer 10

4-8 times greater (the greater the increase the greater the fitness FYI)

Question 11

Label the diagram

Answer 11

Question 12

What are the three improvements in the diagram (don’t explain them, just what they are)?

Answer 12

1 - An atrium

Question 13

How does an atrium improve the hearts ability to pump?

Answer 13

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

Question 14

How does moving the inlet and outlet to the same side of the heart improve the hearts ability to pump?

Answer 14

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

Question 15

How does an auricle improve the hearts ability to pump

Answer 15

Increasing the size of the atrium allows more blood to get into the heart/get pumped

Question 16

Label the diagram, What view of the heart is this?

Answer 16

Anterior view

Question 17

What are the pressures of the ventricles?

Answer 17

Right = 27mmHg

Left = 120mmHg

Question 18

What are the pressures of the atriums?

Answer 18

Right = 5mmHg

Left = 8mmHg

Question 19

Why are the vena cava’s pointing up and down but the pulmonary arteries pointing to the side?

Answer 19

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.

Question 20

Label the diagram. What is the view of this heart?

Answer 20

Posterior view

Question 21

Label the diagram

Answer 21

Question 22

What are the two valves in the heart called and where are they? What are they called together?

Answer 22

Tricuspid valve in the right atrium/ventricle border, Bicuspid/Mitral valve in the left atrium/ventricle border

Atrioventricular (AV) valves

Question 23

What are the AV vales made of?

Answer 23

Fibrous connective tissue

Question 24

What is connected to the AV valves to stop them from flipping upwards?

Answer 24

Chordae tendineae (Tendinous cords)

Question 25

What is the purpose of Chordae tendineae?

Answer 25

Stops the valves and therefore prevent blood from betting forced into the atrium during contraction

Question 26

What controls the force applied to the Chordae tendineae? What is their purpose?

Answer 26

Papillary muscles

Tense as the valves are pushed back preventing the tendons to be too long therefore blood leaks back into atrium

Question 27

Are the AV valves relatively large or small? Why?

Answer 27

They are quite large

This is because the inlets are large

Question 28

At birth what is the relative size of the ventricles? Why does it change as you get older?

Answer 28

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

Question 29

What are the peak pressures in the left and right ventricle?

Answer 29

Left = 120mmHg

Right = 27mmHg

Question 30

What are the relative wall thicknesses of the ventricles?

Answer 30

Left:right, 3:1

Question 31

What are the inlet and outlet valves called?

Answer 31

Inlet: Atrioventricular valves

Outlet: Semi-lunar valve

Question 32

Where are the outlet valves in the heart?

Answer 32

At the base of the pulmonary trunk and aorta

Question 33

Which of these valves is an outlet and inlet valve and what are their proper names?

Answer 33

1 is an inlet/Atrioventricular valve

Question 34

What is the relative size of outlet valves compared to inlet valves? Why?

Answer 34

They are smaller

There is a smaller diameter in the arteries as blood is being transported at a higher pressure