Autotroph

Autotrophs are organisms that produce their food from inorganic resources. The term "autotroph" is derived from the basic words 'auto' for 'self' and 'troph' for 'food'. Thus, an autotroph is a living organism that feeds itself without the help of other living things.

In this article, we are going to discuss the autotroph and also its types and examples.

What is an Autotroph?

An autotroph is a living organism that produce their food from light, water, carbon dioxide, or other molecules. Autotrophs are also referred to as producers because they make their own food. Autotrophs, as producers, are essential components of any ecosystem. They produce nutrients that are required by all other forms of life on the planet.

Autotrophs are essential since no other kind of life can exist without them. For example, suppose plants did not produce sugars from carbon dioxide gas and sunlight through photosynthesis. In that case, there will be no herbivorous animals or predatory animals that eat herbivores and carnivores.

As a result, autotrophs are commonly referred to as 'producers'. It's because they are the basis of an ecosystem's energy pyramid, providing the fuel that all heterotrophs require to survive.

How do autotrophs produce their own food?

Plants are the most prevalent autotrophs since they produce their food via photosynthesis. A chloroplast is a specialized organelle within a plant's cell that allows it to synthesize nutrients from light. These organelles create glucose, a basic sugar utilized for energy, and oxygen as a byproduct when they combine water and carbon dioxide. Glucose is a source of sustenance for the producing plant and an energy source for the plant's consumers. Algae, plankton, and some bacteria are examples of autotrophs that utilize photosynthesis.

Several types of bacteria may use chemosynthesis to create nutrients. For example, chemosynthesis produces carbon dioxide and energy by combining molecules such as methane or hydrogen sulfide with oxygen instead of using light, water, and carbon dioxide. This process is also known as oxidation.

Types of Autotrophs

Autotrophs are classified into three groups based on the sort of energy they use to produce organic compounds. Chemoautotrophs use chemical energy, while photoautotrophs use light energy.

1. Photoautotrophs
2. Chemoautotrophs

Photoautotrophs

The most common autotrophs are photoautotrophs. The majority of photoautotrophs are plants and some photosynthetic microorganisms. Photoautotrophs have chloroplasts that transform photon energy into chemical energy stored in sugars and energy-containing molecules. It is also referred as photosynthesis. Photosynthesis also necessitates water use, which plants get via their roots, and atmospheric carbon dioxide, which plants get via their leaves. Photosynthesis also results in the formation of inorganic oxygen.

Plants and other photoautotrophs provide important ecological roles in almost all terrestrial environments. Photoautotrophs provide energy and nutrients to animals by converting light energy into energy stored in energy-rich molecules. Photosynthesizers are the basis of most ecological food webs.

Many photoautotrophs use carbon from the atmosphere to produce sugars and other compounds that store the Sun's energy in their chemical bonds. They accomplish this by absorbing Carbon dioxide (CO₂) molecules produced by nonliving natural processes and releasing Oxygen (O₂) molecules.

Chemoautotrophs

Chemoautotrophs are bacteria that get their energy from the chemical energy contained in inorganic materials. They make sugars form of carbon dioxide, an inorganic substance. Chemoautotrophs are most typically found in deep water locations where there is no sunlight. Many people must live near deep-sea volcanic vents that produce enough heat to allow rapid metabolism.

Chemoautotrophs get their energy from volatile molecules like molecular hydrogen, ferrous iron, elemental sulfur, ammonia, and hydrogen sulfide. It allows them to live in environments that would be harmful to many other organisms and those that lacked sunlight. Bacteria and archaebacteria are the most common chemoautotrophs, as their metabolisms are not enough to support multicellularity.

Sulfur reducers are chemoautotrophs that get their energy from sulfur compounds in the environment. Sulfur reducers could be found on the ocean floor near active volcanoes and vents where inorganic sulfur from the Earth's core is discharged into the sea. These bacteria could be live as symbiotic organisms with tubeworms and clams located near vents, giving them a nutrition source. Extremely high temperatures are ideal for these chemoautotrophic bacteria. Many of these bacteria, known as extremophiles, are classed as belonging to the Domain Achaea.

Examples of Autotrophs

There are various examples of autotrophs. Some of them are as follows:

Green Algae

Photoautotrophs include green algae, which we may recognize as pond scum. Green algae could resemble cyanobacteria, the first common living form on Earth, which grew in mats and began turning Earth into a world via an oxygen atmosphere.

Plants

Plants are photoautotrophs, with a few exceptions (such as the Venus flytrap, which can eat insects). They make sugars and other vital elements for life by capturing photons and storing their energy using pigments like chlorophyll. When animals ingest plants, they are able to use the energy and organic components for their own purposes.