Apedia Logo Apedia
Join

Choose Language

Select your preferred reading language
🇬🇧
English
✔
🇮🇳
हिन्दी
✔
✕
Full View
Geography
Ecology
EN हिंदी
✕
UPSC Prelims 2025 Paper-I 📅 25 May, 2025

With reference to the planet Earth, consider the following statements:
I. Rain forests produce more oxygen than that produced by oceans.
II. Marine phytoplankton and photosynthetic bacteria produce about 50% of world oxygen.
III. Well-oxygenated surface water contains several folds higher oxygen than that in atmospheric air.

Which of the statements given above is/are correct?

A
I and II
B
II only
C
I and III
D
None of the above statements is correct
Result Summary
Logo

APEDIA

UPSC Prelims
2025 • 25 May, 2025 • Paper-I
With reference to the planet Earth, consider the following statements:
I. Rain forests produce more oxygen than that produced by oceans.
II. Marine phytoplankton and photosynthetic bacteria produce about 50% of world oxygen.
III. Well-oxygenated surface water contains several folds higher oxygen than that in atmospheric air.

Which of the statements given above is/are correct?
Correct Answer
II only
Statement I is wrong; the oceans produce 50 to 80 percent of Earth oxygen, far more than rainforests. Statement II is correct. Statement III is wrong; atmospher......
Ref/Book : UPSC Prelims 2025
Ref. Subject Geography
Chapter -
Ref. Topic Ecology
Pg. No -
💡 Analysis & Explanation
Introduction ▼
Statement I is wrong; the oceans produce 50 to 80 percent of Earth oxygen, far more than rainforests. Statement II is correct. Statement III is wrong; atmospheric air contains roughly 21 percent oxygen, whereas water contains dissolved oxygen in mere parts per million (ppm), which is drastically lower.
← Prev
40 / 100
Next →