Question

How do heterotrophs get their energy?

Answer 1

Heterotrophic organisms are the ones- that are unable to process their own food and derive nutrition from complex organic molecules. They occupy higher trophic levels in the food chain.

Complete answer:
Nutrients are the substances that provide nourishment to an organism for growth, survival, development, reproduction, and other important metabolic reactions and process in the body. They break down food to provide energy to the organisms.
The process of obtaining or utilizing the nutrients or food particles and obtaining energy by their breakdown is called nutrition. It occurs in five basic steps in animals-
1)Ingestion
2)Digestion
3)Absorption
4)Assimilation
5)Excretion.

Based on the mode of nutrition, the organisms can be divided as- Autotrophs and Heterotrophs.
Autotrophs- These organisms can obtain their own food by using inorganic sources. They use light, water, carbon dioxide, and other minerals or chemicals to produce their food. These organisms are primary producers and occupy the first trophic level in the food chain. Examples of autotrophic organisms are- all green plants and few other bacteria like Cyanobacteria. These organisms obtain their own food by the process of photosynthesis.
Heterotrophs- These organisms cannot prepare their own food and depends on other organisms for their food. They feed on the complex organic molecules prepared by the autotrophs. They generate energy through the process of respiration and release carbon dioxide. The energy from the sun is passed to the heterotrophs through autotrophs. They feed on plant or animal matter. They occupy the higher trophic levels of the food chain and are mostly the primary, secondary or tertiary consumers.

Based on their source of food, heterotrophs can be divided into various categories like-
1)Herbivores- Feed on green plants.
2)Omnivores- Feed on green plants and animal’s meat.
3)Carnivores- Feed on animal’s meet.
4)Detritivores- Feed on dead and decaying organisms.
5)Scavengers- Feed on the remains of carnivores and omnivores.
6)Decomposers- Decompose dead plants and animals.

Heterotrophs play a significant role in maintaining the ecosystem by releasing carbon dioxide into the atmosphere through respiration. The released carbon dioxide is used by the autotrophs- to perform photosynthesis. They play an important role in nutrients and minerals recycling and in maintaining the fertility of the soil. The decomposers are also responsible for lowering the number of wastes found in the atmosphere by decomposition. Organic molecules are also formed through the process of decomposition, which is given back to the atmosphere.

Hence, the correct answer is option ()

Note: The Sun is considered the ultimate source of energy for all the living organisms- present in the earth’s atmosphere. The autotrophs synthesize food or sugar molecules using sunlight as the main source of energy through- photosynthesis. The heterotrophs consume the autotrophs or the sugar molecules. The heterotrophs perform cellular respiration to break down these complex organic molecules and release energy in the form of ATP. Thus, indirectly or directly, all autotrophs and heterotrophs- depend on the sun as the source of energy.