Question

The vast majority of bacteria are

• A. Photoautotrophs
• B. Chemoautotrophs
• C. Heterotrophs
• D. Chemotrophs

Answer 1

The correct option is C

Heterotrophs

The correct option is option C.

Explanation of the correct option:

1. The organisms which can not prepare their own food but depend on other organisms such as plants and animals for deriving nutrition are called heterotrophs.
2. The single-celled microorganism found in deserts, hot springs, and marshy areas are known as bacteria.
3. The majority of bacteria are heterotrophic i.e. can not prepare their own food
4. Heterotrophic bacteria feed on dead plants and animals, thus they are referred to as decomposers.
5. Heterotrophic bacteria are found in soil, food, and water, and can act as a parasite thereby causing diseases in humans, animals, and plants.
6. Some of the heterotrophic bacteria are Xanthomonas, Salmonella, Agrobacterium, and Pseudomonas.

Explanation for the incorrect options:

Option A:

1. The organisms that can prepare their own food in the presence of sunlight are called photoautotrophs.
2. Some photoautotrophic bacteria are Cyanobacteria, purple sulfur, and green sulfur bacteria.

Option B:

1. Chemoautotrophs, are the organisms that derive energy from inorganic chemical compounds such as carbon dioxide to produce organic compounds such as carbohydrates, lipids, and proteins.
2. Chemoautotrophs are capable of making their own food from carbon dioxide fixation.
3. Some chemoautotrophs are Bacteria such as Methanogens and Nitrosomonas.

Option D:

1. Chemotrophs are organisms that can obtain energy by the oxidation of reduced organic or inorganic compounds.
2. Nitrobacter, Nitrosomonas are chemotrophs.

Final Answer: the vast majority of bacteria are heterotrophs.