(i) The first step is the break-down of glucose into pyruvate. (ii) Glucose is a six-carbon molecule and pyruvate is a three-carbon molecule. (iii) The breakdown of glucose take place in the mitochondria. (iv) The breakdown of pyruvate using oxygen ...

The oxygen rich blood from the lungs comes to the Left Atrium when it dilates. The right Atrium receives the deoxygenated blood from the body.