Question

Organism 'X' is a multicellular, heterotrophic, eukaryote with a chitinous cell wall. In which kingdom will you place it?

• A. Monera
• B. Animalia
• C. Protista
• D. Fungi

Hint:

Cell wall composition is a major diagnostic tool: Plants = Cellulose, Fungi = Chitin, Bacteria = Peptidoglycan, Animals = No cell wall.

Answer 1

The Correct Option is D

Step 1: Understanding the Problem:
R.H. Whittaker's Five Kingdom Classification system categorizes living organisms based on cell structure, body organization, mode of nutrition, and cell wall composition.
Step 2: Approach and Formula:
Cross-reference the four specific distinguishing traits provided (multicellular, heterotrophic, eukaryotic, chitinous wall) against the characteristics of the five kingdoms.
Step 3: Detailed Explanation:
- Monera: Unicellular, prokaryotic organisms. (Mismatches "eukaryote").
- Protista: Primarily unicellular eukaryotes. While some are heterotrophic, they lack chitinous walls.
- Animalia: Multicellular, heterotrophic eukaryotes, but they strictly lack any cell wall.
- Fungi: They are eukaryotes, predominantly multicellular (except yeast), strictly heterotrophic (absorptive/saprophytic), and critically, their cell walls are composed of a tough, complex sugar called chitin.
All four traits uniquely and exclusively point to Kingdom Fungi.
Step 4: Final Answer:
The organism belongs to Kingdom Fungi.