Question

True or False

The citric acid cycle consumes more energy than it produces.

Answer 1

False

The citric acid cycle (also known as the Krebs Cycle) is actually a part of the much larger process called cellular respiration, the process where your body harvests energy from the food you eat.

Energy shuttles:

1. NADH: An energy shuttle which delivers high energy electrons to the electron transport chain where they will eventually power the production of 2 to 3 ATP molecules. When this electron shuttle is not carrying high energy electrons, meaning it has been oxidized (lost its electrons), it is left with a positive charge and is called NAD^\text{+}​+​​start superscript, plus, end superscript.
2. FADH_{2}​2​​start subscript, 2, end subscript: Another energy shuttle that carries high energy electrons to the electron transport chain, where they will ultimately drive production of 1 to 2 ATP molecules. The oxidized form of FADH_{2}​2​​start subscript, 2, end subscript is FAD and happens just like in NADH.

High energy molecules:

1. ATP: The basic energy currency of the cell. It’s a form of energy that cells can use right away.
2. GTP: Similar to ATP, GTP can be easily converted to ATP in the cell.

whenever the cycle will complete, there have a production of high energy molecules.

which means that the citric acid cycle consumes less energy than it produces.