Chapter 5 – (b) Environmental Pollution | Life Science Solution Class 10

Objective-type questions (MCQ)

Question 1

Answer

Biosphere

Question 2

1. Animals
2. Plants
3. Man
4. None of these.

Answer

Man

Question 3

1. CO₂
2. O₂
3. CO
4. Sulphur.

Answer

CO (carbon monoxide)

Question 4

Answer

Automobile exhausts and chemicals liberated industry

Question 5

1. Detergent
2. Pesticides
3. Industrial wastes
4. Automobile exhausts.

Answer

Industrial wastes

Question 6

Which one of the diseases caused due to air pollution ?-

1. Lung cancer
2. Cholera
3. Headache
4. Dysentery.

Answer

Lung cancer

Question 7

1. Growth of organisms due to food consumption
2. Increase in the size of the population
3. Blowing up of environmental issues by man
4. Increase in concentration of non-degradable pollutants as they pass through the food chain.

Answer

Increase in concentration of non-degradable pollutants as they pass through the food chain.

Question 8

Green house effect is due to-

1. CO₂
2. CO
3. NO
4. PO₄

Answer

CO₂ (carbon dioxide)

Question 9

1. lead
2. uranium
3. cobalt
4. all of these.

Answer

lead

Question 10

1. CFC
2. N₂O
3. Ozone
4. SO₂

Answer

SO₂

Question 11

Answer

Phosphates

Explanation:

Phosphates are not an air pollutants, they are a type of water pollutant.

Question 12

1. methane
2. water vapour
3. oxygen
4. carbon monoxide.

Answer

Oxygen

Question 13

1. their pigments
2. excretion of coloured substances
3. formation of coloured chemicals in water facilitated by physiological degradation of algae
4. absorption of light by algal cell wall.

Answer

their pigments

Question 14

Answer

Fresh water lakes.

Question 15

1. CO₂
2. Methane
3. CFCs
4. N₂O.

Answer

Methane

Question 16

1. water
2. planktons
3. small fishes
4. birds.

Answer

Small fishes

Question 17

DDT is-

1. a non-degradable pollutant
2. an antibiotic
3. a biodegradable pollutant
4. not a pollutant.

Answer

non-degradable pollutant

Question 18

Which of the following pollutant is released from the moving motor vehicles ?-

1. NO₂
2. CO
3. CO₂
4. NO.

Answer

CO₂

Fill in the blanks

Question

1. The entire inhabited part of the earth where living organisms exist along with the abiotic environment is called ____.
2. The materials which cause pollution of the environment are called ____.
3. Major cause of air pollution in big cities is ____.

Answer

1. Biosphere
2. Pollutants
3. Automobile exhausts and industrial emissions.

Very Short-Answer (VSA) type questions

Question 1

What do you mean by Environmental Pollution? 

Answer

Environmental pollution refers to the introduction of harmful pollutants into the environment that cause negative effects on living organisms and their natural surroundings.

Question 2

Answer

Phytoplankton is microscopic aquatic organisms that perform photosynthesis and form the base of many aquatic food webs.

Question 3

What is zooplankton? 

Answer

Zooplankton refers to small floating aquatic animals that are unable to swim against the current and drift along with the water.

Question 4

Name two pollutants.

Answer

Two pollutants are:

1. Carbon monoxide
2. Sulphur dioxide

Question 5

Mention the full name of CFC. 

Answer

Question 6

What is water pollution?

Answer

Water pollution refers to the contamination of water bodies such as lakes, rivers, oceans, and groundwater with harmful substances, chemicals, and pollutants that degrade their quality and make them unfit for use.

Question 7

What is solid waste? 

Answer

Solid waste is the unwanted or useless solid materials generated from human activities in residential, industrial or commercial areas.

Question 8

State the expanded form of DDT. 

Answer

DDT stands for Dichlorodiphenyltrichloroethane.

Question 9

Give a definition of an ecosystem. 

Answer

An ecosystem refers to a community of living organisms that interact with each other and with their physical environments, such as air, water, and soil.

Question 10

What is a biosphere? 

Answer

The biosphere is part of the Earth’s surface and atmosphere where living organisms exist. It includes all living beings, their interactions with each other and with their environment, and the ecosystems they form.

Question 11

Answer

Environment pollution is defined as any undesirable change in the physical, chemical or biological characteristics of any component of the environment (air, water, soil) which can cause harmful effects on various forms of property.

Question 12

 What do you mean by biomagnification? 

Answer

Biomagnification is the process by which certain harmful substances such as heavy metals or persistent organic pollutants, increase in concentration at higher trophic levels in a food chain.

Question 13

What do you mean by the greenhouse effect? 

Answer

The gradual increase of the earth’s temperature due to the presence of certain gases like carbon dioxide, methane and chlorofluorocarbons in the atmosphere is known as the greenhouse effect.

Question 14

What is an algal bloom? 

Answer

The rapid growth of algae due to the addition of artificial or natural substances to an aquatic system is called algal bloom. Algal form a dense sheath at the surface water.

Question 15

What is water pollution?

Answer

Water pollution refers to the contamination of water bodies such as rivers, lakes, oceans, and groundwater by harmful substances or pollutants, making the water unfit for human and animal use.

Short Answer (SA) type questions

Question 1

What do you mean by biomagnification?

Answer

Biomagnification is the process by which the concentration of certain pollutants increases with each level of the food chain. This occurs when organisms absorb pollutants faster than they can excrete them, leading to an accumulation in their tissues.

Question 2

Answer

Question 3

What do you mean by anthropogenic pollution and Natural pollution?

Answer

Anthropogenic pollution refers to pollution caused by human activities, such as industrialization, transportation, and urbanization, which release large quantities of pollutants into the environment.

Natural pollution, on the other hand, is caused by natural processes, such as volcanic eruptions, wildfires, and dust storms, which can release large quantities of particulate matter, gases, and other pollutants into the atmosphere.

Question 4

What is afforestation?

Answer

Afforestation is the process of establishing a forest or stand of trees, in an area where there was no forest. It involves planting trees on land that has not been forested for a long time, has never been forested, or has been deforested due to natural or human-induced causes.

Question 5

What is greenhouse effect? What are its consequences?

Answer

The greenhouse effect refers to the warming of the earth’s surface and lower atmosphere caused by the presence of certain gases in the atmosphere, known as greenhouse gases.

Question 6

Mention three causes of deforestation.

Answer

Three causes of deforestation are:

1. Clearing of forests for agricultural or industrial purposes.
2. Logging and harvesting of timber for various commercial uses.
3. Expansion of human settlements and infrastructure development.

Long Answer (LA) type questions

Question 1

Classify the pollutants with the help of a chart.

Answer

• Air pollutants: Carbon monoxide, nitrogen dioxide, sulfur dioxide, ozone, particulate matter, lead
• Water pollutants: Oil, sewage, fertilizers, pesticides, heavy metals
• Soil pollutants: Industrial waste, agricultural waste, radioactive waste
• Noise pollution: Traffic noise, construction noise, industrial noise
• Light pollution: Overexposure to artificial light at night
• Heat pollution: Excessive heat from industrial processes or climate change

Question 2

Answer

Air pollution is caused by the release of various pollutants into the atmosphere, which can have harmful effects on human health and the environment. Some of the major air pollutants include:

1. Particulate Matter: Particulate matter is a mixture of tiny particles that can be suspended in the air. These particles can be released from natural sources such as dust storms and wildfires, but they are also produced by human activities such as industrial processes and transportation.
2. Nitrogen oxides (NOx): These are a group of gases, including nitrogen dioxide and nitric oxide, which are produced by the burning of fossil fuels in vehicles and power plants. They contribute to the formation of smog and acid rain and can cause respiratory problems.
3. Sulfur dioxide (SO₂): SO2 is produced by the burning of fossil fuels, particularly coal. It can cause respiratory problems and contribute to the formation of acid rain.
4. Ozone (O₃): Ozone is a gas that is formed when nitrogen oxides and volatile organic compounds (VOCs) react in the presence of sunlight. It is a major component of smog and can cause respiratory problems.
5. Carbon monoxide (CO): CO is produced by the incomplete burning of fossil fuels, particularly in vehicles. It is a poisonous gas that can cause headaches, nausea, and even death.

Question 3

How is water polluted? Discuss the harmful effects of water pollution.

Answer

Water can be polluted by various human activities such as industrial effluents, agricultural run-off, sewage disposal, oil spills, and dumping of chemical waste. Some of the harmful effects of water pollution are:

1. Adverse effects on aquatic life: Water pollution can have a significant impact on aquatic organisms, including fish, insects, and plants. Polluted water can cause a decrease in oxygen levels in the water, which can lead to the death of fish and other aquatic organisms.
2. Health hazards: Polluted water can cause various water-borne diseases such as cholera, typhoid, and dysentery. These diseases are caused by microorganisms that thrive in contaminated water.
3. Toxic chemicals: Industrial waste dumped into water bodies can contain toxic chemicals such as lead, mercury, and cadmium, which can cause serious health problems if consumed by humans or animals.

Question 4

Discuss the greenhouse effect on the biological system.

Answer

The greenhouse effect on the biological system

1. The greenhouse effect increases the temperature of the Earth’s surface and oceans, which can cause harm to many living organisms.
2. Climate change due to the greenhouse effect can alter habitats and affect the migration patterns of various species.
3. Increased temperatures can cause heat stress, dehydration, and other physiological stressors in animals and plants.
4. Changes in precipitation patterns due to the greenhouse effect can also affect plant growth, soil moisture, and water availability for organisms.
5. The greenhouse effect can also lead to more extreme weather events such as floods, droughts, and hurricanes, which can have severe impacts on the biological systems.

Question 5

Write about the sources and nature of pollutants in water.

Question 6

Answer

The effects of water pollution are

1. Loss of aquatic life and biodiversity
2. Contamination of drinking water sources
3. Spread of waterborne diseases
4. Algal blooms and depletion of dissolved oxygen levels
5. Disruption of aquatic ecosystems and food chains.

Question 7

Mention the basic groups of pesticide chemicals with two examples for each.

Answer

The basic groups of pesticide chemicals are:

1. Organochlorines – Examples include DDT, Aldrin
2. Organophosphates – Examples include Malathion, Diazinon
3. Carbamates – Examples include Carbaryl, Methomyl
4. Pyrethroids – Examples include Permethrin, Cypermethrin
5. Neonicotinoids – Examples include Imidacloprid, Clothianidin

Question 8

Write about greenhouse gases. 

Answer

Greenhouse gases are those gases that trap heat in the Earth’s atmosphere, contributing to the greenhouse effect and causing global warming. The major greenhouse gases include carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), and fluorinated gases such as hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF₆). These gases are released into the atmosphere through various human activities such as the burning of fossil fuels, deforestation, agriculture, and industrial processes. The concentrations of these gases have been increasing rapidly over the past few decades, leading to significant climate change and its associated impacts on ecosystems and human societies.

Question 9

Write about the cause of global warming.

Answer

Global warming is caused by the increased concentration of greenhouse gases in the atmosphere, primarily due to human activities such as burning fossil fuels, deforestation, and industrial processes. These greenhouse gases trap heat in the Earth’s atmosphere, causing a rise in global temperatures. The main greenhouse gases responsible for global warming are carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), and fluorinated gases such as hydrofluorocarbons (HFCs) and perfluorocarbons (PFCs). The burning of fossil fuels, such as coal, oil, and gas, is the largest contributor to greenhouse gas emissions, accounting for around 80% of total emissions. Deforestation, agriculture, and other industrial processes also contribute to the release of greenhouse gases.

Question 10

What are the strategies may be taken into consideration to check global warming?

Answer

There are several strategies that can be taken into consideration to check global warming, some of which are:

1. Use of renewable energy sources: The use of renewable energy sources like solar, wind, hydropower, geothermal, and biomass can help reduce the emission of greenhouse gases.
2. Energy efficiency: Improving energy efficiency in buildings, transportation, and industries can reduce energy consumption and hence the emission of greenhouse gases.
3. Afforestation and reforestation: Planting trees can help absorb carbon dioxide from the atmosphere and reduce the concentration of greenhouse gases.
4. Carbon capture and storage: Carbon capture and storage (CCS) is a technology that captures carbon dioxide from industrial processes and stores it underground or in deep ocean waters.

Question 11

Answer

Deforestation refers to the permanent removal of trees and forests, typically to clear land for agricultural, industrial, or urban development purposes. It can also be caused by natural disasters such as wildfires, disease, and insect infestations.

Some of the causes of deforestation are:

1. Agricultural expansion: Forests are cleared to make way for agricultural land, particularly for cash crops such as soybeans, palm oil, and coffee.
2. Logging: Trees are harvested for their wood to make paper, furniture, and other products.
3. Urbanization: Trees are cleared to make way for buildings, roads, and other infrastructure.
4. Mining: Forests are cleared to access minerals and other resources that lie beneath the land.
5. Natural disasters: Forests can be destroyed by wildfires, disease, and insect infestations.

The effects of deforestation are:

1. Loss of biodiversity: Deforestation destroys habitats and reduces biodiversity, leading to the extinction of plant and animal species.
2. Climate change: Deforestation contributes to climate change by reducing the amount of carbon dioxide that trees can absorb from the atmosphere.
3. Soil erosion: Without tree roots to hold soil in place, deforested areas are prone to erosion and landslides.
4. Water cycle disruption: Deforestation can disrupt the water cycle, leading to reduced rainfall and increased soil dryness.
5. Economic impact: Deforestation can have a negative impact on the economy, particularly for communities that rely on forests for food, shelter, and income.

Question 12

Discuss briefly the greenhouse effect.

Answer

The greenhouse effect is a natural process that occurs when certain gases in the Earth’s atmosphere, known as greenhouse gases, trap heat from the sun and prevent it from escaping back into space. These gases include carbon dioxide, methane, nitrous oxide, and fluorinated gases.

While the greenhouse effect is a natural phenomenon, human activities, particularly the burning of fossil fuels, have significantly increased the number of greenhouse gases in the atmosphere, leading to an enhanced greenhouse effect and global warming.

The consequences of global warming can be severe, including rising sea levels, more frequent and severe weather events such as hurricanes, floods, and droughts, loss of biodiversity, and negative impacts on human health.

Question 13

How water and air are polluted? 

Answer

WATER POLLUTION:

1. Domestic waste: The disposal of household wastes and sewage into water bodies.
2. Industrial waste: The disposal of industrial waste into water bodies.
3. Agricultural waste: The use of fertilizers, pesticides, and insecticides in agriculture which leads to runoff and seepage into water bodies.
4. Oil spills: Accidental release of crude oil or petroleum products into water bodies.
5. Landfills: Improper disposal of solid waste in landfills which can contaminate nearby groundwater.

AIR POLLUTION:

1. Automobile exhaust: The emissions from vehicles, especially those running on fossil fuels like petrol and diesel.
2. Industrial emissions: The release of pollutants from industries like chemical plants, oil refineries, and power plants.
3. Agricultural practices: The use of fertilizers and pesticides in agriculture, as well as the burning of crop residue.
4. Residential fuel use: The burning of wood, charcoal, and other fuels in homes for cooking and heating.
5. Natural sources: Volcanic eruptions, wildfires, and dust storms can release pollutants into the air.

Question 14

Write about global warming gases.

Answer

Global warming gases, also known as greenhouse gases, are a group of gases that trap heat in the Earth’s atmosphere and contribute to the phenomenon of global warming. The major global warming gases include carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), and fluorinated gases. These gases are released into the atmosphere from various human activities, including the burning of fossil fuels, deforestation, agriculture, and industrial processes.

Carbon dioxide (CO₂) is the most significant global warming gas and is primarily emitted from burning fossil fuels such as coal, oil, and natural gas. Methane (CH₄) is a potent greenhouse gas and is primarily emitted from agricultural activities such as livestock farming and rice paddies, as well as from landfills and natural gas production. Nitrous oxide (N₂O) is primarily emitted from agricultural activities such as the use of nitrogen fertilizers, as well as from fossil fuel combustion and industrial processes. Fluorinated gases, including hydrofluorocarbons (HFCs) and sulfur hexafluoride (SF₆), are synthetic gases used in various industrial applications and are very potent greenhouse gases.