Ecology Basics MCQs

Statement 1 is incorrect because oceans, through phytoplankton, produce roughly half of global oxygen, exceeding rainforest output. Statement 2 is correct.

Statement 1 overstates rainforest contribution relative to oceans, and Statement 3 is factually wrong since atmospheric air contains about 21% oxygen while dissolved oxygen in water is measured in parts per million.

Statement 2 is well-established in marine biology; phytoplankton and photosynthetic bacteria do contribute roughly half of global oxygen production.

Mahua flowers are pollinated by multiple generalist visitors including bats and insects; there is no obligate one-to-one insect relationship.

Sandalwood is a hemiparasitic tree pollinated by various generalist insects and does not display obligate co-evolution with a single pollinator.

Silk cotton (Bombax) is typically pollinated by birds, bats, and generalist insects rather than a single co-evolved insect partner.

Statement 3 is incorrect; male leopards actively scent-mark trees and rocks to define territory, much like lions do.

Statement 3 is wrong. Leopards are solitary and territorial, and scent marking is a key behaviour used by male leopards.

Statement 3 is factually incorrect since male leopards prominently use scent marking, urine spraying, and claw marks to demarcate territory.

None of these organisms is a bird. Cicadas are hemipterans, froghoppers are cercopids, and pond skaters are gerrid bugs.

These are not aquatic vertebrates. Pond skaters glide on the water surface but are insects, not fish.

All three are insects belonging to different families within the class Insecta, not reptiles.

All three groups contain poisonous species, not just one. For example, poison dart frogs, pufferfish, and certain butterfly species like the monarch are toxic.

All three groups have poisonous representatives, not just two.

All three groups contain well-documented poisonous species in the animal kingdom.

None of the pairings is correct, so even one correct match is an overstatement.

All three pairings are incorrect; each animal is native to a different country than the one listed.

Indri is found in Madagascar (not Brazil), Elk in North America/Eurasia (not Indonesia), and Bonobo in the Democratic Republic of Congo (not Madagascar).

All three are legumes belonging to the family Fabaceae (pea family), not just one.

All three plants are members of the pea family, not just two.

All three are well-known leguminous crops classified under Fabaceae.

All four statements are correct, not just one. Mushrooms exhibit a remarkable diversity of biochemical properties.

Each of the four properties is well-documented in mycology, so only two correct is an undercount.

All four, not three, are valid. Bioluminescent mushrooms (e.g., Mycena chlorophos) are documented alongside the other properties.

This describes the hydrological cycle function of wetlands, not the filtration or purification role implied by the kidney analogy.

This describes the role of wetlands in supporting food webs, not their purification or waste-filtering function.

Sedimentation and soil stabilization relate to geomorphic functions, not the toxin-removal role that kidneys perform.

Protozoa also form symbiotic relationships — for example, termite gut flagellates help digest cellulose.

Cnidarians like corals host symbiotic zooxanthellae algae, so excluding them is incorrect.

Fungi form mycorrhizal associations and lichens, which are textbook symbiotic relationships, so excluding them is wrong.

Jellyfish are carnivorous predators that capture zooplankton and small fish using nematocysts, and seahorses are predators of small crustaceans — neither is a detritivore.

Jellyfish and seahorses are both predators, not detritivores. Including them is incorrect.

Jellyfish and seahorses are active predators in marine ecosystems and do not feed on dead organic matter.

Statements 2 and 4 are also correct. Herbivorous fish (e.g., parrotfish) and viviparous snakes (e.g., boa constrictor) are well known.

Statement 1 is also true. Green sea turtles are primarily herbivorous, feeding on seagrass and algae.

This omits statements 1 and 3, both of which are correct. Green turtles eat seagrass, and dugongs/manatees are herbivorous marine mammals.