Animal transportation

Question 1

Define single circulation?

Answer 1

Single circulation is when blood flows through the heart once every complete circuit.

Question 2

Define double circulation?

Answer 2

Is when blood passes through the heart twice every complete circuit

Question 3

Explain how the heart functions?

Answer 3

• the deoxygenated blood incoming from the body flows into the right atrium via the vena cava
• once the right atrium has filled with blood, the blood is pushed through the tricuspid
  Valve and into the right ventricle.
• ventricle contractions occurs and the blood is pushed into the pulmonary artery through the semi lunar valve which prevents the blood from flowing backwards to the heart.
• the blood travels to the lungs and moves through the capillaries passing the Alveoli.
• the oxygenated blood returns to the left atrium via the pulmonary vein.
• It passes to through the bicuspid wall and into the left ventricle.
• the thicker muscle walls of the ventricle contract to push the blood forcefully into the aorta and around the body.
• the semi lunar valve in the aorta prevents the blood from flowing back down the heart.