An autotroph is an organism that can produce its own food using inorganic substances. In contrast, heterotrophs are organisms that cannot produce their own nutrients and require the consumption of other organisms to live. Autotrophs are important parts of the ecosystem known as producers, and are often the food source for heterotrophs. Autotroph definition
Main conclusions: Autotrophs
- Autotrophs use inorganic material to produce food through a process known as photosynthesis or chemosynthesis.
- Examples of autotrophs include plants, algae, plankton and bacteria.
- The food chain consists of producers, primary consumers, secondary consumers and tertiary consumers. Producers, or autotrophs, are at the bottom of the food chain, while consumers, or heterotrophs, are at the top.
definition of autotroph
Autotrophs are organisms that create their own food using inorganic material. They can do this using light, water and carbon dioxide, in a process known as
photosynthesis , or using a variety of chemicals through a method called chemosynthesis . As producers, autotrophs are essential building blocks of any ecosystem. They produce nutrients that are necessary for all other types of life on the planet. Autotroph definition
How do autotrophs make their own food?
Plants are the most common types of autotrophs and use photosynthesis to make their own food. Plants have a specialized organelle inside their cells called a chloroplast , which allows them to produce nutrients from light. In combination with water and carbon dioxide, these organelles produce glucose , a simple sugar used for energy, as well as oxygen as a byproduct. Glucose not only provides nutrition for the producing plant, but is also a source of energy for the consumers of those plants. Other examples of autotrophs that use photosynthesis include algae, plankton, and some types of bacteria.
Different types of bacteria can use chemosynthesis to produce nutrients. Instead of using light in combination with water and carbon dioxide, chemosynthesis uses chemicals like methane or hydrogen sulfide along with oxygen to produce carbon dioxide and energy. This process is also known as oxidation. These autotrophs are often found in extreme environments to find the chemicals needed for food production. These environments include underwater hydrothermal vents, which are cracks in the seafloor that mix water with underlying volcanic magma to produce hydrogen sulfide and other gases. Autotroph definition
autotrophs vs. heterotrophs
Heterotrophs differ from autotrophs in that they cannot produce their own food. Heterotrophs require the consumption of organic, rather than inorganic, material to create the nutrients necessary for life. Therefore, autotrophs and heterotrophs play different roles within an ecosystem. In any food chain, producers, or autotrophs, and consumers, or heterotrophs, are needed. Heterotrophs include herbivores, carnivores, and omnivores. Herbivores are primary plant eaters and consume autotrophs as primary consumers. Carnivores consume herbivores, and therefore can be secondary consumers. Tertiary consumers are carnivores or omnivores that eat smaller secondary consumers. Omnivores are meat and plant eaters and therefore use autotrophs and other heterotrophs for food.
Examples of autotrophs
The simplest example of autotrophs and their food chain includes plants such as grass or small shrubs. Using soil water, carbon dioxide and light, these plants perform photosynthesis to provide their own nutrients. Small mammals such as rabbits are primary consumers that eat the surrounding flora. Snakes are secondary consumers that eat rabbits , and large birds of prey such as eagles are tertiary consumers that consume snakes. Autotroph definition
Phytoplankton are the main autotrophs in aquatic ecosystems. These autotrophs live in oceans across the land and use carbon dioxide, light and minerals to produce nutrients and oxygen. Zooplankton are primary consumers of phytoplankton, and smaller filter fish are secondary consumers of zooplankton. Small predatory fish are tertiary consumers in this environment. Larger predatory fish or marine mammals are other examples of tertiary consumers that are predators in this ecosystem. Autotroph definition
Autotrophs that use chemosynthesis, such as the deep-sea bacteria described above, are a final example of autotrophs in the food chain. These bacteria use geothermal energy to produce nutrients from oxidation using sulfur. Other species of bacteria can act as primary consumers of autotrophic bacteria through symbiosis. Instead of consuming autotrophic bacteria, these bacteria obtain nutrients from autotrophic bacteria. bacteria, keeping them inside their bodies and providing protection from the extreme environment in return. Secondary consumers in this ecosystem include snails and mussels, which consume these symbiotic bacteria. Carnivores, like octopuses, are tertiary consumers that prey on snails and mussels.