Describe or diagram the relationship between catabolic pathways, anabolic pathways and the ATP-ADP cycle. Include in your answer an explanation of the role each of these plays in the metabolism of a cell

Question

What will be an ideal response?

Answer 1

All the chemical reactions that take place in a cell, including those reactions which release energy and those reactions which require energy, are collectively termed metabolism. Most metabolic reactions in a cell are organized into sets of reactions called biochemical pathways. Catabolic pathways break down substances and release energy. Anabolic pathways build new molecules from existing molecules, using energy in the process. The energy released from catabolic pathways is temporarily stored in a molecule called ATP. ATP has three phosphate groups. The terminal phosphate can be removed from the ATP to form ADP and release energy. This released energy can be used for anabolic reactions. ADP must continually be recharged, so a constant input of energy into the cell is required. The cycling of ADP to ATP, driven by energy from catabolic reactions and then back to ADP as the energy is released to fuel anabolic reactions, is a continual process in every cell.