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Difference Between Autotrophs and Heterotrophs

Autotrophs

The organisms which can use materials from inorganic sources to produce their own food are known as Autotrophs.

The word “Autotrophs” is a combination of two words; “auto” + “troph.” It comes from the root words “auto,” which means “self,” and “troph,” which means “food.”

In simple words, the organisms which feed itself without any other organism’s help are known as Autotrophs.

For example, all green plants. In the green plants, chlorophyll pigment which is present in the plant cell that helps to synthesis their own food by absorbing energy from the sunlight. All the autotrophs are known as producers, and in the food web, they are placed at the primary level.

Without autotrophs, the other forms of life cannot exist so, the autotrophs are extremely essential. Autotrophs are also known as “producer” because the autotroph form the base of an ecosystem’s energy pyramid and give the fuel that needs to exist for all the heterotrophs (heterotrophs are the organisms that consume their food from others).

An autotroph uses carbon dioxide from simple substances like carbon dioxide to produce complex organic compounds (like proteins, fats, and carbohydrates).

There are two types of Autotrophs:

1. Photoautotrophs
2. Chemoautotrophs

Heterotrophs

A group of organisms which get their food from other organisms and are unable to produce their own food are known as Heterotrophs.

Heterotrophs are those organisms which are unable to prepare their own food, and for their food, they depend on green plants or producers and other animals. This mode of nutrition is called the heterotrophic mode of nutrition. To give a constant supply of new organic molecules, heterotrophs depend on autotrophs. In the food web, heterotrophs are considered as consumers, and they are placed at a secondary or tertiary level.

The example of heterotrophs comprises all the non-green plants and animals, including human beings.

There are two types of Heterotrophs:

1. Photoheterotrophs
2. chemoheterotrophs

In various ways, heterotrophs get benefits from photosynthesis:

• By using oxygen for the process of cellular respiration.
• By consuming plants directly like herbivores.
• By indirectly killing, attacking, and consuming other herbivorous animals (non-vegetarians) or both plants and animals (omnivores).

Difference between Autotrophs and Heterotrophs

Basis for Comparison	Autotrophs	Heterotrophs
Meaning	The organisms which can use materials from inorganic sources to produce their own food are known as Autotrophs.	Heterotrophs are those organisms which are unable to prepare their own food, and for their food, they depend on green plants or producers and other animals.
Source of energy	In autotrophs, sunlight and chemical reaction are the source of energy.	In heterotrophs, autotrophs are the source of energy, whether it is direct or indirect.
Trophic level	In the food chain, the autotrophs form the lowest tropic level.	In the food chain, the heterotrophs form the second or tertiary level.
Dependency	Autotrophs are able to produce their own food, so the autotrophs are independent.	Heterotrophs are not able to produce their own food due to which the heterotrophs are dependent on autotrophs directly/indirectly.
Role	The autotrophs behave like a producer.	The Heterotrophs behaves like a consumer.
Solar energy	In some autotrophs, solar energy can be stored.	In Heterotrophs, solar energy cannot be store or use.
Types	There are two types of autotrophs: Photoautotrophs Chemoautotrophs	There are two types of heterotrophs: Photoheterotrophs Chemoheterotrophs
Organisms	Generally, the autotrophs are certain kind of bacteria, algae as well as plants.	Generally, the heterotrophs are fungi, animals, and some bacteria.
Carbon dioxide	As a source of carbon, autotrophs use inorganic carbon.	As a source of carbon, the heterotrophs use organic carbon.
Examples	Cyanobacteria, algae, plants, etc.	Animals, humans, fungi, heterotrophic bacteria.
Photosynthetic pigments	Usually, photosynthetic pigments are present in Autotrophs.	In heterotrophs, photosynthetic pigments are absent.
Availability	At a specific time period, autotrophs make food. During the day, plants make food, and the chemoautotrophs rely on the chemical reaction.	Food is available almost any time of the day for heterotrophs.

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