Circulatory System - The Heart

Question 1

what type of circulatory system regarding the heart do mammals have

Answer 1

a double circulatory system

Question 2

what does a double circulatory system describe

Answer 2

heart pumps blood around the body in two circuits

Question 3

how is blood pumped in the first circuit in the double circulatory system

Answer 3

• heart pumps deoxygenated blood to the lungs to take in oxygen
• oxygenated blood returns to the heart

Question 4

how is blood pumped in the second circuit in the double circulatory system

Answer 4

• heart pumps oxygenated blood around all the other organs of the body to deliver oxygen to the body cells
• deoxygenated blood then returns to the heart

Question 5

what type of circulatory system regarding the heart do fish have and how does it work

Answer 5

• a single circulatory system
• deoxygenated blood from the fish’s body travels to the heart which pumps it right round the body again in a single circuit
• through the gills where it picks up oxygen

Question 6

how many chambers and major blood vessels does the mammalian heart have

Answer 6

• 4 chambers

- 4 major blood vessels

Question 7

what does the right atrium of the heart recieve

Answer 7

deoxygenated blood from the body through the vena cava

Question 8

where does the deoxygenated blood from the right atrium move through

Answer 8

the right ventricle, which pumps it to the lungs through the pulmonary artery

Question 9

what does the left atrium of the heart recieve

Answer 9

oxygenated blood from the lungs through the pulmonary vein

Question 10

where does the oxygenated blood from the left atrium move through

Answer 10

the left ventricle, which pumps it out round the whole body through the aorta

Question 11

which ventricle of the heart has a thicker wall and why

Answer 11

• the left ventricle has a thicker wall
• because it has to pump blood around the whole body at high pressure
• where as the right ventricle only has to pump it to the lungs

Question 12

what do valves do

Answer 12

they prevent the backflow of blood in the heart

Question 13

what is cardiac output

Answer 13

the total volume of blood pumped by a ventricle every minute

Question 14

what is the equation for cardiac output

Answer 14

cardiac output = heart rate x stroke volume

cm^3 min^-1 = bpm x cm^3

Question 15

what is the heart rate

Answer 15

the number of beats per minute

Question 16

what is the stroke volume

Answer 16

the volume of blood pumped by one ventricle each time it contracts

Question 17

using cardiac output, heart rate and stroke volume, which of these values is at the top of their formula triangle

Answer 17

cardiac output

Question 18

which two vessels does blood come in from in the heart

Answer 18

• the vena cava on the right side

- the pulmonary vein on the left side

Question 19

which two vessels does blood leave the heart from

Answer 19

• the pulmonary artery on the right side, sending blood to lungs
• the aorta on the left side, sending blood to the body