Test: Respiration in Plants - October 11, 2022 - NEET MCQ

All the energy required for life processes is obtained by the oxidation of some macromolecules that we call as food. All living organisms need energy to carry out daily life activities.

Only green plants and cyanobacteria can prepare their food, by the process of photosynthesis. They trap light energy and convert it into chemical energy that is stored in the bonds of carbohydrates.

Fungi are generally saprophytes which are dependent on dead and decaying matter. Animals are heterotrophic, i.e., they obtain food from plants directly (herbivores) or indirectly (carnivores).

Cellular respiration is the mechanism of breakdown of food materials within the cell to release energy and the trapping of this energy for the synthesis of ATP.

Photosynthesis takes place within the chloroplasts in the eukaryotes whereas the breakdown of complex molecules to yield energy takes place in the cytoplasm and the mitochondria.

The breaking of the C-C bonds of complex compounds through oxidation within the cells, leads to the release of a considerable amount of energy. This process is known as respiration.

Nucleic acids like DNA and RNA are never oxidised to release energy because these are integrated parts of the cell and they are used to carry or express different genes in the human beings which carry out different functions like the formation of proteins, fats and carbohydrates.

ATP or Adenosine Triphosphate acts as the energy currency of the cell. The energy which is released by the oxidation of respiratory substrates is stored in ATP so that we can use it for future purposes.

Carbon skeletons are used as precursors for the biosynthesis of other biomolecules as the oxidation of these carbon skeletons leads to the formation of ATP which is stored by the cells to be utilised in various-energy requiring processes of the organisms.

Plants, unlike animals, have no specialised organs for gaseous exchange but they use stomata and lenticels for this purpose. Plants can easily get along without any specialised respiratory organs.