Plants, algae and some bacteria are said to be autotrophic, as they are able to cook their own food using sunlight, air and water. On the other side, animals such as dogs, lions, cows, horses, etc. are considered heterotrophic because they cannot cook their own food and are directly or indirectly dependent on the nutrition of other organisms.
The way food is assimilated by living organisms, or the way organisms consume food, they are divided into two main categories: heterotrophic and autotrophic. Autotrophs are the main producer for the reason that they are able to cook their own food for energy. In this case, heterotrophs are considered a secondary or tertiary consumer in the food chain.
Our Earth has many organisms, not just people. I wonder what these organisms are getting food for? What are they eating? How do they grow and develop? Thus, organisms were grouped into such categories by observation and according to preference for feeding. Here, we’ll walk through the notable differences between both categories and discuss them briefly.
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Definition of heterotrophs
Heterotroph comes from the Greek word where hetero means “other” and troph means “food .” Thus, we can say that organisms that obtain their energy by feeding on plants, animals and decaying substances are contained in this category.
Sugar + oxygen → carbon dioxide + water + ATP
This reaction is called cellular respiration. It is a process used for energy production, where ATP, known as adenosine triphosphate, is the primary form of energy used by heterotrophs.
- Herbivores: These are animals that only eat plants to get their energy. Examples are cows, deer, rhino, etc.
- Carnivores: These species are dependent on the flesh of other animals to extract their energy. Examples are lion, tiger, fox, etc.
- Omnivores: These organisms mainly derive their energy from both types, which means they can feed on both plants and animals. Examples are people.
- Decomposers: They are saprophytic in that they get their energy requirements from dead and decaying substances. An example is fungus.
Definition of autotrophs
Autotroph also comes from the Greek word, where auto means “self” and troph means “feeding.” Hence, these types are considered to be the main producers who can cook their own food using sunlight, water and air.
Mostly green-leaved plants, from mosses to long trees, algae, phytoplankton and some bacteria, use a process called photosynthesis , where plants get energy from the sun and use it to convert carbon dioxide from the air and water from the soil into nutrients called glucose.
This glucose is a form of sugar that provides energy for plants. This glucose is also used to make cellulose, which helps in building cell walls in plants. They don’t really need to move anywhere in search of food.
Hence, from the above reaction, we can say that they convert the energy of light into chemical energy.
Some autotrophs use a different process called chemosynthesis, in which they use the energy of chemical reactions to produce food instead of getting it from the sun. Organisms living in extreme conditions, such as bacteria living in active volcanoes or in the deep ocean, use this process.
Pitcher plants are an exception as they are classified as mixotrophic, as they get their nourishment from both the plants and insect eating.
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Key differences between heterotrophs and autotrophs
The following are significant differences between heterotrophs and autotrophs, depending on the method of feeding, dependence, the process of obtaining food, etc.
- Animals such as cow, dog, elephant, rhino, lion, etc. are said to be just as heterotrophic as these animals indirectly depend on food for others; while green plants, algae and a small number of bacteria are considered autotrophic, as they are able to prepare their own food through the process of photosynthesis, which requires sunlight, air, water and sunlight.
- Heterotrophs are considered consumers and are housed at the secondary or tertiary level in the food web, while autotrophs are the main producers.
- Heterotrophs do not contain chloroplasts, chlorophyll and, therefore, are not able to prepare food on their own, and also depend on others for energy. Autotrophs contain chloroplast, chlorophyll and are therefore capable of producing their own food and depend on sunlight, air and water for cooking.
- Heterotrophs can go from one place to another for food, autotrophs cannot move.
- Heterotrophs get their energy directly or indirectly from other organisms, while autotrophs get their energy from inorganic sources, where they convert the energy of light (sunlight) into chemical energy.
Heterotrophs are dependent on autotrophs for food, but autotrophs are not.
Conclusion
From the above discussion, it can be said that both types of nutrition are equally important in maintaining the biosphere’s food chain. How every living being trusts each other in one way or another. We can say that autotrophs are called “self-feeders”, and heterotrophs are called “other feeders.”
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