Question

Which one is not correct for oxidation of food?
a. It is a multiple process.
b. All released energy is in the form of ATP.
c. Trapped energy is further used for biosynthesis of other molecules.
d. Oxidisable compound is known as respiratory substrate.

Answer 1

Hint: All the energy needed to carry on life comes from the oxidation of food. Plants can make their own food by trapping light energy from the sun and converting it to chemical energy by the process of photosynthesis.

Complete answer:
Plants make their own food which is further consumed by herbivores and other organisms. So it won’t be wrong to say that all the energy required for life comes from plants by the process of photosynthesis. Plants make food for us that is broken down/ oxidised so that it can release energy which is required for our life processes. Oxidation of food takes place in the mitochondria of eukaryotes and chloroplast of plants. The release of energy by breaking C-C bonds in the macromolecules by oxidation is known as Respiration and the macromolecules are known as respiratory substrates. Energy after oxidation is released step by step not at once completely.

Energy produced by the oxidation of food is used for the synthesis of ATP (Adenosine triphosphate) which is the energy currency of the cell. Energy present in ATP is utilised in various life processes and also for the synthesis of several molecules in the cell.

Hence, the correct answer is option (B).

Additional information:
Food is said to be oxidised when it loses all its electrons to some other molecule. And hence the molecule that obtains electrons is in reduced form and the food that gave its electrons is in oxidised form.
ATP has a base adenine and three phosphate groups.
ATP is used in metabolic processes of the body, active transport of substances across the cell membrane, for mechanical work (movement of muscles).

Note: ATP (Adenosine triphosphate) is not a storage molecule, carbohydrates are. ATP is produced from carbohydrates when the cells need energy and ATP delivers the required energy. This is the reason why biologists refer to ATP as, energy currency of the cell.