The figure given below shows the steps in glycolysis. Fill in the missing steps A, B, C, D and also indicate whether ATP is being used up or released at step E?

Respiration is an energy releasing and enzymatically controlled catabolic process which involves a step-wise oxidative breakdown of organic substances inside living cells.

In this statement about respiration explain the meaning of

1) Step-wise oxidative breakdown, and

2) Organic substances (used as substrates).

Comment on the statement – Respiration is an energy producing process but ATP is being used in some steps of the process.

Why is respiratory pathway referred to as an amphibolic pathway? Explain.

We commonly call ATP as the energy currency of the cell. Can you think of some other energy carriers present in a cell? Name any two.