During a long-term ecological study, students examined organisms collected. Class 9
During a long-term ecological study, students examined organisms collected. Class 9
Question 1.
During a long-term ecological study, students examined organisms collected from three different environments - a freshwater pond, damp soil near decaying logs, and the digestive tract of animals. Instead of naming organisms directly, scientists recorded only structural, cellular and nutritional features as given in the table below. Class 9
| Organisms | Key Observations |
| P | Microscopic; no true nucleus; rigid cell covering; survives high salinity and temperature |
| Q | Multicellular; filamentous body; cell wall present; no chlorophyll; grows on dead organic matter |
| R | Unicellular; true nucleus; contractile vacuole present; moves using flagella; shows photosynthesis in light but heterotrophic in the absence of light |
| S | Multicellular; well-differentiated tissues; backbone present; aquatic respiration during early life stage |
| T | Acellular; contains genetic material; remains inactive outside a host cell |
The students realised that some organisms fit neatly into Whittaker's five kingdom classification, while others challenged the very basis of this classification.
Based on the case study, answer the following questions:
(i) Identify one organism that clearly belongs to the Kingdom Fungi. State one observation that supports your answer.
Answer:
Organism Q belongs to Kingdom Fungi.
Supporting observation: It is multicellular with a filamentous body (mycelium), has a cell wall (made of chitin in fungi), has no chlorophyll (so it cannot photosynthesise - it is heterotrophic), and grows on dead organic matter (saprophytic - characteristic of fungi as decomposers).
(ii) Which organism would be placed in the Kingdom Monera? Mention one characteristic that justifies this placement. Class 9
Answer:
Organism P would be placed in Kingdom Monera. Justifying characteristic: It has no true nucleus (no membrane-bound nucleus) - it is a prokaryote. Kingdom Monera is the only kingdom consisting of prokaryotic organisms. Additionally, it has a rigid cell covering and can survive high salinity and temperature, which is characteristic of extremophile bacteria.