[Mission 2022] QUIZ – 2022: INSIGHTS STATIC QUIZ, 3 June 2022 – Environment – INSIGHTSIAS

Solution: d)

Exotic species introduced to new environments often reset the ecological conditions in that new habitat, threatening the species that exist there; this is the reason that they are also termed invasive species.

Invasive species that are closely related to rare native species have the potential to hybridize with the native species; harmful effects of hybridization have led to a decline and even extinction of native species.

Invasive species can change the food web in an ecosystem by destroying or replacing native food sources. The invasive species may provide little to no food value for wildlife.

Lakes and islands are particularly vulnerable to extinction threats from introduced species.

Solution: c)

“Bioluminescent organisms are usually found in the ocean environments, but they are also found on terrestrial environments. The colour of the light emitted by the organism depends on their chemical properties.”

In the case of fungi, the luminescence comes from the enzyme, luciferase. “The [green] light emits when luciferans is catalysed by the enzyme luciferase, in the presence of oxygen. During the chemical reaction, several unstable intermediate products are released as excess energy that makes them visible as light.

Bioluminescent mushrooms may glow for a number of reasons. The simplest explanation could be that bioluminescence attracts insects, which helps in dispersing spores. It may also be a mechanism for the organism to protect itself from frugivorous (or fruit-eating) animals.

Solution: a)

A parasite is an organism that lives in or on another living organism, deriving nutrients from it. In this relationship the parasite benefits, but the organism being fed upon, the host, is harmed. The host is usually weakened by the parasite as it siphons resources the host would normally use to maintain itself. The parasite, however, is unlikely to kill the host. This is because the parasite needs the host to complete its reproductive cycle by spreading to another host.

The reproductive cycles of parasites are often very complex, sometimes requiring more than one host species. A tapeworm is a parasite that causes disease in humans when contaminated, undercooked meat such as pork, fish, or beef is consumed. The tapeworm can live inside the intestine of the host for several years, benefiting from the food the host is bringing into its gut by eating. The parasite moves from species to species as it requires two hosts to complete its life cycle.

Solution: b)

A keystone species is a species which has a disproportionately large effect on its natural environment relative to its abundance.

Keystone species play a critical role in maintaining the structure of an ecological community, affecting many other organisms in an ecosystem and helping to determine the types and numbers of various other species in the community.

Solution: d)

A niche is the unique functional role or place of a species in an ecosystem. It is a description of all the biological, physical and chemical factors that a species needs to survive, stay healthy and reproduce.

A niche is unique for a species, which means no two species have exact identical niches. Niche plays an important role in conservation of organisms.

If we have to conserve species in its native habitat we should have knowledge about the niche requirements of the species and should ensure that all requirements of its niche are fulfilled.