Explain the flow of blood through the human heart.

The first thing I make sure the student understands, prior to any technical knowledge about the subject or question at hand, is how key shaping their reply directly towards the exam standards / framework is in ensuring their answer achieves the highest number of marks possible. This means discussing the different key words used by exam questions, and thus the nature of the answer they are expected to deliver (e.g. 'describe', 'explain', 'state' etc), as well as training the student to phrase his/her answers via the use of specific key words & terminology (this is essential in Biology, just as dates and names are in History, for example) - basically, just ensuring the student understands they are being assessed at passing the exam as much as they are being tested on their knowledge of the actual subject. To answer the question (have put the key words in bold): the heart can be classified into two halves - the right half deals with collecting de-oxygenated blood (i.e. blood returning from the body) and pumping it to the lungs to be re-oxygenated - this is the pulmonary circuit - and the left half deals with collecting this re-oxygenated blood and pumping it back around the body - this is the systemic circuit. Each half contains an atrium and a ventricle, which are separated by valves that prevent the blood from flowing backwards. The de-oxygenated blood collects in the right atrium via the superior vena cava and is pumped through the pulmonary artery to the lungs by the right ventricle. It returns to the left atrium via the pulmonary vein, and is then pumped through the aorta to the rest of the body by the left ventricle.