Difference between Autotrophs and Heterotrophs

All living organisms in the earth need energy to survive. Based on how they get their food all organisms are divided into two major categories: Autotrophs and Heterotrophs. Autotrophs are organisms which prepare their own food and Heterotrophs depend on other organisms for their food and energy.

In this article we will discuss what are autotrophs, what are heterotrophs and what are the differences between autotrophs and heterotrophs.

What are Autotrophs

Autotrophs are organisms which can produce their own food from natural sources like water, light, carbon dioxide (CO2) and chemicals. Because autotrophs produce their own food sometimes they are called primary producers.

Based on the source of organisms used to prepare their own food, autotrophs are divided into two types: Photoautotrophs and Chemoautotrophs.

Photoautotrophs: These include plants, algae, and bacteria. They use sunlight and other inorganic substances such as carbon dioxide, water to produce food through a process called photosynthesis. Examples: Green plants, algae, and cyanobacteria.

Chemoautotrophs: Chemoautotrophs are organisms that prepare their own food using energy obtained through chemical reactions instead of sunlight. They use inorganic substances such as hydrogen sulfide, ammonia, hydrogen, and sulfur. Examples: Deep-sea bacteria found near hydrothermal vents, Sulfur-oxidizing bacteria, Nitrifying bacteria.

What are Heterotrophs

Heterotrophs are organisms that depend on other organisms for their food and energy. The word heterotrophic derived from the ancient Greek word “hetero” means “other” and “trophe” means “nourishment”. There are three types of heterotrophs: herbivores, carnivores, omnivores and detritivores.

Herbivores: Herbivores are organisms which eat plants and plant parts such as grass, leaves, fruits, and seeds. Example: Cow, goat, deer, rabbit.

Carnivores: Carnivores organisms eat other animals such as herbivores and a few other small animals for food. Examples: Lion, tiger, and eagle.

Omnivores: Omnivores are organisms which eat both plants like herbivores and animals like carnivores. Examples: Humans, bears, and crows.

Detritivores: Detritivores are organisms that feed on dead plants and animals, decaying plant and animal matter as well as other organic wastes. Examples: Earthworms.

Differences between Autotrophs and Heterotrophs