Circulatory System - The Heart Flashcards
what type of circulatory system regarding the heart do mammals have
a double circulatory system
what does a double circulatory system describe
heart pumps blood around the body in two circuits
how is blood pumped in the first circuit in the double circulatory system
- heart pumps deoxygenated blood to the lungs to take in oxygen
- oxygenated blood returns to the heart
how is blood pumped in the second circuit in the double circulatory system
- 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
what type of circulatory system regarding the heart do fish have and how does it work
- 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
how many chambers and major blood vessels does the mammalian heart have
- 4 chambers
- 4 major blood vessels
what does the right atrium of the heart recieve
deoxygenated blood from the body through the vena cava
where does the deoxygenated blood from the right atrium move through
the right ventricle, which pumps it to the lungs through the pulmonary artery
what does the left atrium of the heart recieve
oxygenated blood from the lungs through the pulmonary vein
where does the oxygenated blood from the left atrium move through
the left ventricle, which pumps it out round the whole body through the aorta
which ventricle of the heart has a thicker wall and why
- 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
what do valves do
they prevent the backflow of blood in the heart
what is cardiac output
the total volume of blood pumped by a ventricle every minute
what is the equation for cardiac output
cardiac output = heart rate x stroke volume
cm^3 min^-1 = bpm x cm^3
what is the heart rate
the number of beats per minute
what is the stroke volume
the volume of blood pumped by one ventricle each time it contracts
using cardiac output, heart rate and stroke volume, which of these values is at the top of their formula triangle
cardiac output
which two vessels does blood come in from in the heart
- the vena cava on the right side
- the pulmonary vein on the left side
which two vessels does blood leave the heart from
- the pulmonary artery on the right side, sending blood to lungs
- the aorta on the left side, sending blood to the body
