[Mission 2023] STATIC QUIZ, 02 March 2023 – Environment

Solution: c)

Phytoplanktons are food factories of the ocean, it fixes atmospheric carbon dioxide in large quantities (Carbon Sink) and produce food. So, if phytoplanktons are removed completely it leads to catastrophic failure of ocean ecosystem. It doesn’t influence the density of ocean water.

Solution: c)

In an aquatic ecosystem, grazing food chain is the major conduit for energy flow. As against this, in a terrestrial ecosystem, a much larger fraction of energy flows through the detritus food chain than through the grazing food chain.

When energy is passed in an ecosystem from one trophic level to the next, only ten percent of the energy will be passed. Around 90% of energy will be lost.

Solution: b)

Nitrogen is one of the essential constituents of all living organisms as part of proteins, chlorophyll, nucleic acids and vitamins.

The atmospheric nitrogen cannot be taken directly by plants and animals.

Certain bacteria and blue green algae present in the soil fix nitrogen from the atmosphere and convert into compounds of nitrogen

Lightning also fixes atmospheric nitrogen.

Nitrogen is one of the essential constituents of all living organisms as part of proteins, chlorophyll, nucleic acids and vitamins.

The atmospheric nitrogen cannot be taken directly by plants and animals. Once nitrogen is converted into these usable compounds, it can be utilised by plants from the soil through their root system.

Nitrogen is then used for the synthesis of plant proteins and other compounds. Animals feeding on plants get these proteins and other nitrogen compounds.

When plants and animals die, bacteria and fungi present in the soil convert the nitrogenous wastes into nitrogenous compounds to be used by plants again. Certain other bacteria convert some part of them to nitrogen gas which goes back into the atmosphere.

As a result, the percentage of nitrogen in the atmosphere remains more or less constant.

Solution: a)

Clownfish breed only in sea anemones, sharing a symbiotic bond. “It is a strong, obligate symbiosis,”

“Clownfish shelter in the anemone and are the only fish that do not get stung by the nematocysts of the anemone. The anemone benefits because clownfish can defend the anemone from fish that might eat it. They never live anywhere but, in the anemone”.

And now the anemones, like coral reefs in general, are under direct threat from the impacts of climate change. It works like this: The anemones share another symbiotic bond, with algae. Under stress in warming waters, the algae leave the anemones. If the algae stay away too long, the anemone starve to death, which leaves the clownfish without a home.

Solution: a)

Standing crop is defined as the total amount or number of living things or of one kind of living thing (such as an uncut farm crop, the fish in a pond, or organisms in an ecosystem) in a particular area at any given time.