UPSC Prelims 2003 Q99: Environment & Ecology – Biodiversity & Conservation
Consider the following statements:
1. The common blue green algae Spirogyra and Ulothrix are found in both fresh water ponds and
oceans.
2. The chameleon can look ahead with one eye, and at the same time look behind with another.
Which of these statements is/are correct?
- (a) Only 1
- (b) Only 2
- (c) Both 1 and 2
- (d) Neither 1 nor 2
Answer: (b) Only 2
Explanation
Algae and the chameleon
| Statement | Verdict |
|---|---|
| 1. Spirogyra and Ulothrix are found in both fresh water and oceans | False: they are fresh water algae |
| 2. A chameleon can look ahead with one eye and behind with the other | True — its eyes move independently |
Only statement 2 is correct.
Answer: (b) Only 2.
Why each option is right or wrong
- (a) Incorrect. Spirogyra and Ulothrix are fresh water algae.
- (b) CORRECT. Only statement 2 is correct.
- (c) Incorrect. Statement 1 is false.
- (d) Incorrect. Statement 2 is true.
Key point
Spirogyra: fresh water green alga with spiral chloroplast; Ulothrix: filamentous.
Remember
A chameleon's eyes move independently.
Common mistakes
- Thinking these green algae live in oceans too.
- Doubting the chameleon's independent eyes.
- Mixing green algae with seaweeds (brown and red).
Exam tip
Ocean algae: Sargassum (brown), Gelidium (red).
Sources
- NCERT Class XI Biology — Plant Kingdom
- Encyclopaedia Britannica — Spirogyra