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Q1Environment·Ecology BasicsPYQ 2025
With reference to the planet Earth, consider the following statements:
1. Rain forests produce more oxygen than that produced by oceans.
2. Marine phytoplankton and photosynthetic bacteria produce about 50% of world's oxygen.
3. Well-oxygenated surface water contains several folds higher oxygen than that in atmospheric air.
Which of the statements given above is/are correct?
- A1 and 2
- B2 onlyCorrect
- C1 and 3
- DNone of the above statements is correct
Explanation
Correct. Marine phytoplankton and cyanobacteria produce approximately 50% of Earth's oxygen. Rainforests do not outproduce oceans, and dissolved oxygen in surface water is far lower than atmospheric oxygen concentration.
Q2Environment·Ecology BasicsPYQ 2024
Which one of the following shows a unique relationship with an insect that has co-evolved with it and that is the only insect that can pollinate this tree?
- AFigCorrect
- BMahua
- CSandalwood
- DSilk cotton
Explanation
Correct. Fig trees (Ficus) have an obligate mutualism with fig wasps (family Agaonidae); each fig species is pollinated exclusively by its specific wasp partner.
Q3Environment·Ecology BasicsPYQ 2024
Consider the following statements:
1. Lions do not have a particular breeding season.
2. Unlike most other big cats, cheetahs do not roar.
3. Unlike male lions, male leopards do not proclaim their territory by scent marking.
Which of the statements given above are correct?
- A1 and 2 onlyCorrect
- B2 and 3 only
- C1 and 3 only
- D1, 2 and 3
Explanation
Correct. Lions breed throughout the year without a fixed season, and cheetahs lack the laryngeal anatomy to roar. Statement 3 is wrong because male leopards do scent-mark their territories.
Q4Environment·Ecology BasicsPYQ 2024
The organisms "Cicada, Froghopper and Pond skater" are:
- ABirds
- BFish
- CInsectsCorrect
- DReptiles
Explanation
Correct. Cicadas (order Hemiptera), froghoppers (family Cercopidae), and pond skaters (family Gerridae) are all insects.
Q5Environment·Ecology BasicsPYQ 2024
Consider the following:
1. Butterflies
2. Fish
3. Frogs
How many of the above have poisonous species among them?
- AOnly one
- BOnly two
- CAll threeCorrect
- DNone
Explanation
Correct. Some butterflies (e.g., monarch) are toxic from plant alkaloids, certain fish (e.g., pufferfish) carry tetrodotoxin, and many frogs (e.g., poison dart frogs) secrete potent skin toxins.
Q6Environment·Ecology BasicsPYQ 2024
Consider the following pairs:
Country - Animal found in its natural habitat
1. Brazil - Indri
2. Indonesia - Elk
3. Madagascar - Bonobo
How many of the pairs given above are correctly matched?
- AOnly one
- BOnly two
- CAll three
- DNoneCorrect
Explanation
Correct. Indri is endemic to Madagascar, Elk are native to North America and parts of Eurasia, and Bonobos are found only in the Democratic Republic of Congo.
Q7Environment·Ecology BasicsPYQ 2024
Consider the following plants:
1. Groundnut
2. Horse-gram
3. Soybean
How many of the above belong to the pea family?
- AOnly one
- BOnly two
- CAll threeCorrect
- DNone
Explanation
Correct. Groundnut (Arachis hypogaea), horse-gram (Macrotyloma uniflorum), and soybean (Glycine max) all belong to the family Fabaceae, commonly known as the pea or legume family.
Q8Environment·Ecology BasicsPYQ 2023
Consider the following statements:
1. Some mushrooms have medicinal properties.
2. Some mushrooms have psycho-active properties.
3. Some mushrooms have insecticidal properties.
4. Some mushrooms have bioluminescent properties.
How many of the above statements are correct?
- AOnly one
- BOnly two
- COnly three
- DAll fourCorrect
Explanation
Correct. Reishi and turkey tail have medicinal uses; psilocybin mushrooms are psychoactive; Beauveria bassiana-related fungi show insecticidal activity; and species like Mycena chlorophos are bioluminescent.
Q9Environment·Ecology BasicsPYQ 2022
"If rainforests and tropical forests are the lungs of the Earth, then surely wetlands function as its kidneys." Which one of the following functions of wetlands best reflects the above statement?
- AThe water cycle in wetlands involves surface runoff, subsoil percolation and evaporation
- BAlgae form the nutrient base upon which fish, crustaceans, molluscs, birds, reptiles and mammals thrive
- CWetlands play a vital role in maintaining sedimentation balance and soil stabilization
- DAquatic plants absorb heavy metals and excess nutrientsCorrect
Explanation
Correct. Kidneys filter toxins and waste from the body. Similarly, wetland plants absorb heavy metals and excess nutrients, purifying water — making this the best analogy.
Q10Environment·Ecology BasicsPYQ 2021
Which of the following have species that can establish symbiotic relationship with other organisms?
1. Cnidarians
2. Fungi
3. Protozoa
Select the correct answer using the code given below.
- A1 and 2 only
- B2 and 3 only
- C1 and 3 only
- D1, 2 and 3Correct
Explanation
Correct. Cnidarians (e.g., corals with zooxanthellae), fungi (e.g., mycorrhiza, lichens), and protozoa (e.g., gut flagellates in termites) all have well-known symbiotic species.
Q11Environment·Ecology BasicsPYQ 2021
Which of the following are detritivores?
1. Earthworms
2. Jellyfish
3. Millipedes
4. Seahorses
5. Woodlice
Select the correct answer using the code given below.
- A1, 2 and 4 only
- B2, 3, 4 and 5 only
- C1, 3 and 5 onlyCorrect
- D1, 2, 3, 4 and 5
Explanation
Correct. Earthworms, millipedes, and woodlice feed on decaying organic matter and are classic detritivores. Jellyfish and seahorses are predators.
Q12Environment·Ecology BasicsPYQ 2019
Consider the following statements:
1. Some species of turtles are herbivores.
2. Some species of fish are herbivores.
3. Some species of marine mammals are herbivores.
4. Some species of snakes are viviparous.
Which of the statements given above are correct?
- A1 and 3 only
- B2, 3 and 4 only
- C2 and 4 only
- D1, 2, 3 and 4Correct
Explanation
Correct. Green turtles eat seagrass; parrotfish graze on algae; dugongs and manatees are herbivorous marine mammals; and boas and vipers give live birth.