. Distinguish among the terms: Chemoautotroph, Photolithoautotroph, and mixotroph. Cite appropriate examples for each category.

Chemoautotrophs, Photolithoautotrophs, and Mixotrophs are different types of organisms that are categorized based on their energy and carbon sources.

1. Chemoautotrophs: These organisms obtain their energy from chemical reactions and use carbon dioxide as their primary carbon source. They do not require light for energy and instead, they oxidize inorganic substances such as iron, sulfur, and hydrogen gas to obtain energy. An example of a chemoautotroph is Nitrosomonas europaea, a bacterium that oxidizes ammonia into nitrite as a metabolic process.

2. Photolithoautotrophs: These organisms use light as their energy source and inorganic substances as their electron source. They also use carbon dioxide as their primary carbon source. Cyanobacteria, also known as blue-green algae, is an example of a photolithoautotroph. They perform photosynthesis using water as an electron donor, releasing oxygen as a by-product.

3. Mixotrophs: These organisms can use either light or inorganic/organic substances as their energy source, depending on the availability of resources. They can also use either carbon dioxide or organic carbon as their carbon source. An example of a mixotroph is Euglena, a type of single-celled eukaryote that can perform photosynthesis when light is available, but can also consume organic substances for energy when light is not available.