Autotrophic Nutrition
Autotrophic nutrition is a process where organisms produce their own food using inorganic substances like carbon dioxide and water. This process is essential for the survival of plants, algae, and some bacteria. Here are 10 examples of autotrophic nutrition:

1. Photosynthesis
Photosynthesis is the most well-known form of autotrophic nutrition. During this process, plants use sunlight to convert carbon dioxide and water into glucose, releasing oxygen as a byproduct. This glucose serves as the energy source for the plant.

2. Chemosynthesis
Some bacteria and archaea can perform chemosynthesis, where they use energy from chemical reactions to produce organic compounds. This process is commonly found in deep-sea hydrothermal vents.

3. Calvin Cycle
The Calvin Cycle is a series of chemical reactions that take place in the chloroplasts of plants during photosynthesis. It involves the conversion of carbon dioxide into glucose using ATP and NADPH.

4. C3 Plants
C3 plants are a type of plants that use the Calvin Cycle to fix carbon dioxide. Examples include wheat, rice, and soybeans.

5. C4 Plants
C4 plants have a specialized mechanism to fix carbon dioxide in a different cell from where photosynthesis occurs. Corn, sugarcane, and millet are examples of C4 plants.

6. CAM Plants
CAM plants open their stomata at night to take in carbon dioxide and store it as an organic acid. During the day, they close their stomata to prevent water loss and use the stored carbon dioxide for photosynthesis. Pineapples and cacti are examples of CAM plants.

7. Nitrogen Fixation
Some bacteria like Rhizobium can fix atmospheric nitrogen into ammonia, which plants can use as a nutrient. This symbiotic relationship is essential for the growth of leguminous plants like beans and peas.

8. Sulfur Oxidation
Certain bacteria can oxidize sulfur compounds to obtain energy for synthesizing organic molecules. This process is crucial for sulfur cycling in ecosystems.

9. Iron Oxidation
Iron-oxidizing bacteria utilize iron as an energy source to produce organic compounds. They play a vital role in iron cycling in aquatic environments.

10. Hydrogen Oxidation
Hydrogen-oxidizing bacteria can use hydrogen as an energy source to fix carbon dioxide and produce organic matter. These organisms are important in hydrogen cycling in various ecosystems.
These examples highlight the diverse ways in which organisms can perform autotrophic nutrition to sustain themselves and contribute to ecosystem functioning.