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Question #47571
The Question
An artificial marine habitat designed for the commercial extraction of phycocolloids is accidentally colonized by a high density of antibiotic-producing microbes. The secondary metabolites secreted by these microbes cause severe allelopathic growth inhibition of the cultivated Gelidium and Gracilaria. Which of the following correctly identifies the commercial product whose yield will drastically decline, along with its correct biological nature and application?
Options
- A.
Agar; a hydrocolloid derived from the cell wall of red algae, widely used in microbial tissue culture and ice cream preparation.
- B.
Algin; a water-holding substance derived from the cell wall of brown algae, used commercially as a stabilizing agent.
- C.
Carrageen; a hydrocolloid derived from the cell wall of red algae, primarily used as a blood-cholesterol lowering agent.
- D.
Agar; a secondary metabolite derived from the cytoplasm of red algae, used to competitively inhibit other aquatic microbes.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Regulatory_Failure
Understand how NOT, EXCEPT, and logical constraints are used to manipulate exam results.
Concepts Behind This Question
Economic Importance Matrix|Primary vs Secondary Sewage Treatment|Algae
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: The question tests the ability to synthesize ecological amensalism (microbial secondary metabolites inhibiting growth) with the specific economic botany of algae.
The primary trap lies in confusing the structural cell wall polysaccharides of Red Algae (Agar/Carrageen) with the bioactive secondary metabolites of Red Yeast (Monascus purpureus), exploiting the shared 'Red' nomenclature and the multi-chapter context.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Plant Kingdom - Class 11 |
| Concept | Economic Importance Matrix |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |