Question

Explain ( do not simply list) the major nutritional modes found among the prokaryotes.

Answer 1

1) Photoautotroph: Photoautotroph are organisms that carry out photosynthesis. Photoautotrophs are cells that capture light energy, and use carbon dioxide as their main carbon source. Example: Cyanobacteria

2) Chemoautotroph: Chemoautotrophs use inorganic energy sources such as hydrogen sulfide, elemental sulfur, ferrous iron, molecular hydrogen, and ammonia. Carbon dioxide is the major carbon source. Example: Sulfolobus

3) Photoheterotroph: Photoheterotrophs are organisms that capture light energy to convert to chemical energy in the cells, but they get carbon from organic sources. Example: Purple non-sulfur bacteria

4) Chemoheterotroph: Chemotrophs are a class of organisms that obtain their energy through the oxidation of inorganic molecules, such as iron and magnesium. They require organic molecules for both energy and carbon. Example: many bacteria and fungi.