| The pumps | - 2 pumps lying side by side
- The left pump deals with oxygenated blood from lungs
- The right pump deals with de-oxygenated blood from body |
| The chambers | - 4 chambers
- The atrium
- The ventricles
- Connected to large blood vessels, carry blood away or to heart |
| The atria | - Thin-walled
- Elastic, stretches as it collects blood
- Receives blood from veins |
| The ventricles | - Thick muscular walls
- As it has to contract strongly to pump blood some distance, either to lungs or body
- Pumps blood away from heart, into arteries |
| The left + right ventricles | - Right ventricle pumps blood to lungs, has thinner muscular wall
- Left ventricle pumps blood to body, has thicker muscular wall to contract to create enough pressure to pump blood |
| The atria + ventricles working together | - Both atria contract together
- Then both ventricles contract together
- Pump in time with each other
- Pumping the same volume of blood |
| Reasons for two separate pumps | - Blood has to pass through thin capillaries in lungs in order to present a LSA for gas exchange
- So there is a large pressure drop
- So this system allows blood to be returned to the heart to increase pressure before going to rest of body
- Essential to separate oxygenated + de-o blood |
| Pulmonary vessels | - Vessles connecting the heart to the lungs |
| Vessels connected to four chambers | - Aorta
- Vena cava
- Pulmonary artery
- Pulmonary vein |
| Aorta | - Connected to left ventricle
- Carries oxygenated blood to body, accept lungs |
| Vena cava | - Connected to the right atrium
- Brings deoxygenated blood back from tissues, except lungs |
| Pulmonary artery | - Connected to the right ventricle
- Carries deoxygenated blood to lungs
- Where oxygen is replenished + CO2 is removed
- Unusually for artery, it carries de-o blood |
| Pulmonary vein | - Connected to left atrium
- Brings oxygenated blood back from lungs
- Unusually for vein, it carries oxygenated blood |
| Renal artery | - Carries oxygenated blood to kidneys (has urea and salts)
- 2 renal arteries, 1 supplies to right kidney, 1 supplies to the left kidney |
| Renal vein | - Carries deoxygenated blood ( that has had urea + excess salt removed) away from kidneys |
| Hepatic artery | - Artery which supplies oxygenated blood to liver |
| Hepatic vein | - Vein which removes deoxygenated blood away from liver |
| Hepatic portal vein | - Vein which supplies blood rich with digestive products for metabolism |
| Supplying the heart muscle with oxygen | - Heart does not use oxygenated blood that passes through it to meet its own respiratory needs
- Heart muscles supplied by own vessels called, coronary arteries |
| Coronary arteries | - Branch off aorta shortly after it leaves heart
- Blockage of these can cause myocardial infarction |
| Papillary muscles and heart strings | - PM contract
- Creating tension on heart strings
- Stops valves inverting |
