Question

Which of the following is the only group of organisms capable of using inorganic compounds as a source of energy?
A. Eukaryotes
B. Prokaryotes
C. Virus
D. None of the above

Answer 1

Hint: Chemotrophs (or chemosynthetic organisms) get their energy from chemical compounds. Chemotrophs that may use organic compounds as energy sources are referred to as chemoorganotrophs. people who may use inorganic compounds as energy sources are referred to as chemolithotrophs.

Complete step by step answer: On the basis of the energy supply, organisms are classified as organotrophs and lithotrophs. Most prokaryotes and every one non-phototrophic eukaryote use organic compounds as the source of energy and are noted as organotrophs. They oxidise organic compounds throughout respiration and in the process produce gas as the byproduct. However, some true bacteria and Archaea use inorganic compounds as a lepton donor in lepton transport chains and are noted as lithotrophs. None of the eukaryotes falls in this class. Eukaryotes use organic compounds as their source of energy. Example; carbohydrates, lipids, fats, etc. Viruses act as non-living outside the cell. It becomes active once it enters the host cell and utilizes the host cell machinery to replicate itself. Viruses cannot generate or store energy in the form of ATP. Lipids are organic compounds that store most energy. Lipids are fats and their main job in the body is to store energy.
Hence, the correct answer is option B.

Note: Inorganic energy sources are utilized by chemolithotrophic (chemosyn- thetically autotrophic) and mixotrophic microorganisms. The energy from the reaction of inorganic compounds is also obtained aerobically or anaerobically. Certain compounds are said to be organic because of the presence of carbon and hydrogen in their structures.