Question

Most extensive metabolic diversity is found in

• A. Amphibians
• B. Protozoans
• C. Fungi
• D. Bacteria

Answer 1

The correct option is D

Bacteria

The correct option is D.

Explanation of the correct option:

1. Bacteria are the most primitive type of organism.
2. All the anabolic and catabolic reactions that take place in any organism are called metabolic activities.
3. For example respiration, photosynthesis protein synthesis, etc. are the metabolic activities of the cell.
4. Bacteria can be classified according to the metabolic activities found in them:

1. Aerobic bacteria: Aerobic bacteria respirate in the presence of molecular oxygen. These can be facultative or obligate aerobic bacteria. For example Pseudomonas aeruginosa.
2. Anaerobic bacteria: These can respirate in absence of molecular oxygen. These can be facultative or obligate. For example Escherichia coli.
3. Photosynthetic bacteria: Bacteria can perform photosynthesis. In some strains of bacteria, photosynthetic pigments are found. For example Cyanobacteria.
4. Chemosynthetic bacteria: Some autotrophic bacteria can synthesize their food from chemicals like sulfur, iron, nitrogen, and methane. For example Venenivibrio stagnispumantis.
5. Heterotrophic bacteria: These are found in form of parasites, saprophytes, and even symbiotic bacteria. For example Agrobacterium.

Explanation of the incorrect options:

Option A:

1. Amphibians are higher chordates. All of these are heterotrophic.
2. These animals are not metabolically different.
3. These perform aerobic respiration.
4. For example, frogs and salamanders inhale oxygen for cellular respiration.

Option B:

1. Protozoans are eukaryotic unicellular organisms.
2. These are aerobic and can be autotrophic or heterotrophic.
3. For example, Diatoms are autotrophic while slime molds are heterotrophic.

Option C:

1. Fungi is a group of heterotrophic organisms.
2. These perform aerobic respiration but some exceptions like yeast perform anaerobic respiration.
3. Others like Aspergillus and are are aerobic.

Final answer: The most extensive metabolic diversity is found in bacteria.