Important Questions for Class 12 Biology 16th Chapter Environmental Issues MCQ, Very Short, Short Type, Long Type
CBSE Class 12 Important Questions for Class 12 Biology Chapter 16 Environmental Issues all MCQ Type, Very Short Type, Assertion Reason Type, Case Study, Short Type and Long Type Questions with Answers by Expert. Important Questions for Section A, B, C, D Class 12 Biology Chapter 16.
MCQs
(1) Which of the following is used for removing particulate matter from air?
A.) Electrostatic precipitator
B.) Electromagnetic precipitator
C.) Thermomagnetic precipitator
D.) Thermoelectric precipitator
(2) Assertion: Noise is undesired high level of sound
Reason: The Air (Prevention and Control of Pollution) Act was amended in 1987 to include noise as an air
pollutants.
a.) Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
b.) Both Assertion and Reason are correct and Reason is not the correct explanation for Assertion.
c.) If assertion is true but the reason is false.
d.) If both assertion and reason are false
(3) Which of the following metal is used as a Catalytic converter, fitted into automobiles for reducing emission of poisonous gases?
a.) platinum-palladium
b.) rhodium
c.) Both a.) And b.)
d.) None of above
4.) Assertion: mortality offish and other aquatic creatures is high if untreated sewage is discharged into river
Reason: Micro-organisms involved inbiodegradation of organic matter in rivers consume a lot of oxygen resulting in a sharp decline in dissolved oxygen downstream from the point of sewage discharge.
a.) Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
b.) Both Assertion and Reason are correct and Reason is not the correct explanation for Assertion.
c.) If assertion is true but the reason is false.
d.) If both assertion and reason are false
5.) Assertion: If the amount of sewage is significant enough, all of the dissolved oxygen may be eaten, leaving no oxygen for fish and other clean-water creatures to breathe.
Reason: Domestic sewage is rich in nonbiodegradable organic matter and the decomposition of this organic matter by microorganisms requires oxygen.
a.) Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
b.) Both Assertion and Reason are correct and Reason is not the correct explanation for Assertion.
c.) If assertion is true but the reason is false.
d.) If both assertion and reason are false
6.) Smog is a kind of air pollution which is very common in metropolitan cities, is a mixture of
a.) smoke, fog and Sulphur dioxide
b.) smoke and fog only
c.) fog and Sulphur dioxide
d.) smoke and Sulphur dioxide
7.) Water impurities include all except
a.) Suspended solids
b.) Colloidal solids
c.) mineral ores
d.) dissolved impurities
8.) A decrease in ______ is seen du to water contaminated by organic material
a.) DO
b.)BOD
c.) Organic nutrients
d.) O2
9.) ________ is the natural aging of a lake by nutrient enrichment of its water
a.) Biomagnification
b.) Eutrophication
c.) Aggumentation
d.) Bioventing
10.) Which protocol was signed in 1987 (effective in 1989) to control the emission of ozone depleting substances?
a.) Montreal Protocol
b.) Kyoto Protocol
c.) Vienna convention
d.) Rio summit
- Answer in one sentence
Q.1) Give some examples of sources of air pollutants.
Ans. Thermal power plants, smelters, and other businesses discharge particulate and gaseous air pollutants, which mix with innocuous gases like nitrogen and oxygen, from their smokestacks are major source of air pollutant.
Q.2) Which of the following are the most difficult impurities to remove from sewage water?
Ans. The most difficult substances to remove from sewage are dissolved salts such as nitrates, phosphates, and other nutrients, as well as hazardous metal ions and organic compounds.
Q.3) What is Cultural or Accelerated Eutrophication?
Ans. Cultural or Accelerated Eutrophication is the name given to phenomena where Pollutants from man’s activities, such as effluents from companies and residences, can hasten the ageing process of lakes dramatically.
Q.4) What are the three categories of wastes?
Ans. All wastes produced by humans can be divided into three categories: biodegradable, recyclable, and non-biodegradable.
Q.5) What was done in Garhwal Himalayan Chipko Movement?
Ans. Local women shown incredible bravery in 1974 by clinging trees to shield them from contractors’ axes. The Chipko movement has been praised by people all around the world.
Q.6) Give out Two major environmental issues of global nature.
Ans. The growing greenhouse effect, which is warming the Earth, and ozone depletion in the stratosphere are two key worldwide environmental challenges.
- Answer in short
Q.1) What is difference between pollution and pollutants?
Ans. 1.) Any unfavorable alteration in the physical, chemical, or biological features of air, land, water, or soil is referred to as pollution.
2.) Pollutants are agents that cause such an unfavorable transformation to occur.
Q 2) Explain the term biomagnification.
Ans. 1.) The term “biomagnification” refers to the increase in toxicant concentration at successive trophic levels.
2.) This occurs when a harmful material accumulated by an organism is unable to be metabolized or expelled, and consequently passes to the next higher trophic level.
3.) This is a well-known phenomenon with mercury and DDT.
Q.3) Why and when was Montreal Protocol signed?
Ans. 1.) The Montreal Protocol was signed in Montreal, Canada, in 1987 (and went into force in 1989) to regulate ozone-depleting compounds.
2.) Following that, many more attempts were undertaken, and protocols were established that established precise roadmaps for reducing CFC and other ozone depleting chemical emissions, independently for rich and developing countries.
Q.4) What is reforestation?
Ans. 1.) Reforestation is the process of replanting a forest that formerly existed but was depleted due to human activity.
2.) In a deforested region, reforestation may occur naturally.
3.) However, we can hasten the process by planting trees while taking into account the biodiversity that previously existed in the area.
Q.5) Describe Waterlogging and soil salinity problem associated with improper irrigation.
Ans. 1.) Irrigation without sufficient water drainage results in soil waterlogging.
2.) Waterlogging not only harms crops, but it also draws salt to the soil’s surface.
3.) The salt then forms a thin crust on the land surface or begins to accumulate at the plant roots.
4.) Increased salt concentration is detrimental to crop growth and is particularly harmful to agriculture.
5.) Some of the challenges that have arisen as a result of the Green Revolution include waterlogging and soil salinity.
- Answer in brief
Q.1) describe the working of electrostatic precipitator.
Ans.
- The electrostatic precipitator can remove over 99 percent of the particulate matter in a thermal power plant’s exhaust.
- It has electrode wires that are kept at thousands of volts, resulting in a corona that releases electrons.
- Dust particles gain a net negative charge as a result of these electrons attaching to them.
- The charged dust particles are attracted to the grounded collecting plates.
- The air velocity between the plates must be low enough for the dust to fall between them.
- Sulphur dioxide can be removed using a scrubber. The exhaust is scrubbed in a scrubber by a spray of water or lime.
Q.2) How is hospital and e-waste managed?
Ans. 1.) Hospitals produce hazardous waste containing disinfectants and other dangerous chemicals, as well as pathogenic microorganisms.
2.) Such wastes must also be treated and disposed of with care.
3.) The usage of incinerators is critical for hospital waste disposal.
4.) Electronic trash are irreparable computers and other electronic goods (e-wastes). E-waste is either buried in landfills or burned.
5.) Over half of the electronic trash produced in developed regions is sent to developing countries, primarily China, India, and Pakistan, where metals such as copper, iron, silicon, nickel, and gold are recovered during the recycling process.
6.) Unlike developed countries, which have dedicated facilities for e-waste recycling, poor countries’ recycling often requires human labour, exposing workers to harmful compounds found in e-waste.
7.) Recycling is the only option for dealing with e-waste, as long as it is done in an environmentally friendly manner.
Q.3) Describe in detail Radioactive wastes
Ans. 1.) Nuclear energy was once touted as a non-polluting means of generating electricity.
2.) Later on, it was discovered that the utilisation of nuclear energy has two major drawbacks.
3.) The first is unintentional leaking, which happened, and the second is proper disposal of radioactive waste.
4.) The radiation emitted by nuclear waste is particularly harmful to organisms because it generates a high rate of mutations.
5.) Nuclear radiation is harmful at large amounts, but also causes a variety of illnesses at lower doses, the most common of which is cancer.
6.) As a result, nuclear waste is a highly toxic pollutant that must be handled with extreme caution.
7.) After proper pre-treatment, it is suggested that nuclear waste be stored in suitably shielded containers and buried.
8.) After proper pre-treatment, it has been suggested that nuclear waste be stored in suitably insulated containers buried beneath the rocks, roughly 500 metre below the earth’s surface.
9.) However, the public is strongly opposed to this manner of disposal.
Q.4) Give detail explanation of the slash and burn agriculture practice
Ans. 1.) Farmers that practice slash and burn agriculture cut down forest trees and burn the plant leftovers.
2.) The ash is utilized to fertilize the land, which is then used for agricultural or livestock grazing. 3.) The region is left for several years after farming to allow it to recuperate.
4.) After that, the farmers move on to another location and continue the procedure.
5.) When Jhum farming was prevalent in the past, enough time-gap was provided to allow the land to recuperate from the effects of agriculture.
6.) This regeneration phase is obliterated by expanding population and recurrent cultivation, resulting in deforestation.