2019 — 6 questions
Q30. Which ocean is the deepest in the world?
[RPF Constable, 14 February 2019]
(A) Southern Ocean
(B) Indian Ocean
(C) Arctic Ocean
(D) Pacific Ocean
Answer: (D) Pacific Ocean
Explanation: The Pacific Ocean contains the Mariana Trench and Challenger Deep, Earth’s greatest known ocean depth. Deep oceans hold biological and mineral resources that remain incompletely studied. Pressure, darkness and low temperatures make their exploration technically demanding.
Q29. Which of the following seas has especially high salinity?
[RPF Constable, 19 February 2019]
(A) Antarctic seas
(B) Baltic Sea
(C) Arctic Ocean
(D) Mediterranean Sea
Answer: (D) Mediterranean Sea
Explanation: The Mediterranean has relatively high salinity because evaporation is intense and freshwater input is limited compared with the water lost. Water exchange through the Strait of Gibraltar and density differences influence circulation and marine conditions.
Q28. Which Indian location offers significant potential for tidal-energy generation?
[HPSC Assistant Professor Geography, 22 May 2019]
(A) Gulf of Khambhat
(B) Palk Strait
(C) Mouth of the Ganga
(D) Chilika Lake
Answer: (A) Gulf of Khambhat
Explanation: The Gulf of Khambhat has a large tidal range and funnel-shaped coastline, which have long made it a candidate for tidal-energy development. Any infrastructure must be assessed against impacts on marine sediment, coastal ecosystems and navigation.
Q27. The Gulf of Mannar Marine National Park is situated in which state?
[RRB Junior Engineer, 1 September 2019]
(A) Karnataka
(B) Gujarat
(C) Tamil Nadu
(D) Andhra Pradesh
Answer: (C) Tamil Nadu
Explanation: The Gulf of Mannar Marine National Park lies along the Tamil Nadu coast and includes a chain of protected islands. Its habitats include seagrass beds and coral reefs, important for fish populations, dugongs and coastal biodiversity.
Q26. Which present-day ocean is widely regarded as the principal remnant of the ancient Panthalassa Ocean?
[RPSC Second Grade Teacher, 19 February 2019]
(A) Atlantic Ocean
(B) Pacific Ocean
(C) Indian Ocean
(D) Arctic Ocean
Answer: (B) Pacific Ocean
Explanation: Panthalassa was the enormous ocean surrounding the supercontinent Pangaea. Much of its basin evolved into today’s Pacific Ocean. Geological plate movements continually open and close ocean basins, shaping seafloor resources and marine habitats.
Q25. In which of the following states are the Sundarbans mangrove forests located?
[CGPSC State Services Prelims 2018 Cycle, 17 February 2019]
(A) Gujarat
(B) West Bengal
(C) Odisha
(D) Andhra Pradesh
Answer: (B) West Bengal
Explanation: The Sundarbans occupy the lower Bengal delta and extend into Bangladesh, with the Indian part in West Bengal. Their tidal mangroves shelter fish and crustaceans, trap sediment and buffer cyclones. The 2018 recruitment-cycle paper was held in February 2019.
2018 — 5 questions
Q24. Consider statements about coral reefs:
1. Most are in tropical waters.
2. More than one-third of the world’s reefs lie in Australia, Indonesia and the Philippines.
3. They contain more animal phyla than tropical rainforests.
Which are correct?
[UPSC Civil Services Preliminary Examination, 2018]
(A) 1 and 2 only
(B) 3 only
(C) 1 and 3 only
(D) 1, 2 and 3
Answer: (D) 1, 2 and 3
Explanation: Warm, shallow tropical waters support most reef-building corals. Coral reefs are exceptionally diverse and concentrated in parts of the Indo-Pacific, including Australia, Indonesia and the Philippines. Their structure creates numerous specialised habitats despite occupying little ocean area.
Q23. Which ecosystem is regarded as especially stable among the listed choices?
[UPPSC Combined State/Upper Subordinate Services Prelims, 2018]
(A) Marine ecosystem
(B) Forest ecosystem
(C) Mountain ecosystem
(D) Desert ecosystem
Answer: (A) Marine ecosystem
Explanation: The global marine ecosystem is vast and interconnected, which can buffer some environmental fluctuations across space. Nevertheless, specific marine habitats such as coral reefs and mangroves can be fragile and highly susceptible to climate and pollution pressures.
Q22. Which strait lies between India and Sri Lanka?
[Uttar Pradesh Police Constable, 18 June 2018]
(A) Gulf of Mannar
(B) Gulf of Aqaba
(C) Gulf of Mexico
(D) Palk Strait
Answer: (D) Palk Strait
Explanation: The Palk Strait separates southeastern India from northern Sri Lanka. Its relatively shallow waters and nearby island chains shape fisheries and navigation. The Gulf of Mannar lies farther southwest and is known for marine biodiversity.
Q21. The Mariana Trench is located in which ocean?
[RPF Sub-Inspector, 24 December 2018]
(A) Atlantic Ocean
(B) Indian Ocean
(C) Arctic Ocean
(D) Pacific Ocean
Answer: (D) Pacific Ocean
Explanation: The Mariana Trench lies in the western Pacific Ocean and contains the Challenger Deep. Extreme depth creates a unique environment with high pressure and no sunlight. Such habitats are important for understanding deep-sea organisms and geology.
