BIOLOGY MCQ

Both.

Larva of stone fly.

Electronic waste buried in the landfills.

An institution established in India, to center radioactive pollution i.e. Central Environmental and Public Health engineering Institute.

Biochemical oxygen demand is a measure of how much dissolved oxygen is being consumed as microbes break down organic matter. A high demand, therefore, can indicate that levels of dissolved oxygen are falling, with potentially dangerous implications for the river's biodiversity. High biochemical oxygen demand can be caused by high levels of organic pollution, caused usually by poorly treated wastewater; high nitrate levels, which trigger high plant growth.

An endangered species is the species whose population faces a sudden downfall. In the case of wild animals, their habitat is the forest and deforestation of the forests due to ecological disasters, or use of timber for the construction of buildings makes them insecure in their homestead.
Moving away to nearby locations not only disturbs the food chain, breeding grounds and habitats of these wild animals but they are also faced with threats of being hunted and poached for the benefit of the human beings.

Any external substance which changes the natural qualities of water is known as a water pollutant. These can be chemical or biological. These pollutants harm the natural quality of water causing water pollution.

Phenyl

Chlorofluorocarbons or Chlorofluoromethane are also known as freon or aerosols. They are chemicals used as refrigerants, propellants and solid plastic foams.
These chemicals are also released as aerosols by jets flying at high altitudes. Along with nitrogen oxides, chlorofluorocarbons react with ozone of ozonosphere and depletes the same.
Chlorofluorocarbons release reactive chloride which directly reacts with ozone molecules setting a chain reaction.

Blue green and green algal.

Stratosphere.

When forests are destroyed, the atmosphere, water bodies and the water table are all affected.
Trees absorb and retain water in their roots and some of this moisture is transpired into the atmosphere, regulates the water cycle.
When this process is broken, the atmosphere and water bodies begin to dry out.

Humans.

Sources of water pollution to rivers in India are done mainly by the industries and factories pouring untreated chemical waste in the rivers which are highly toxic in nature and another source is sewage waste from domestic households and municipalities goes directly to the river bodies causing major water pollution as it is highly pathogenic in nature.
Bathing is not the major source as it forms a minor portion of the major sewage waste.

Suspended solids.

Large areas will become deserts.

Causes of deforestation are as follows:
Clearing land for human habitation and cultivation.
The need of wood for building houses and factories.
The need of wood for making furniture.
Consequences of deforestation are as follows:
Soil erosion
Depletion of groundwater
Flash flood
Global warming
Loss of biodiversity
Droughts and climate change due to global warming.

Is highly polluted

Excessive use of man made compounds containing both fluorine and chlorine.

Deforestation is the depletion of forest resources. It's main cause is the explosion of human and livestock population with the increased demand requirements of the basic needs.
The major effect of deforestation is the loss of precious wild life, rare species of flora and fauna. Directly or indirectly, deforestation caused intensified soil erosion, accentuated floods, drought and the worst pollution.

Reforestation is restocking of the destroyed forests by planting new trees. The planted trees should generally be of the same species which are found in the forest so that the diversity of the forest can be preserved.
Growing of native species of forest can provide various benefits like the restoration of the soil, rejuvenation of flora and fauna, etc.

Electrostatic precipitator.