Q:

Which of the following is an effect of the high dose of UV-B?

A) Night-blindness B) Snow-blindness
C) Fatigue D) Nausea
 
Answer & Explanation Answer: B) Snow-blindness

Explanation: UV-B is the shorter wavelength of UV. It penetrates deeper into the skin causing aging of skin and cancers. A high dose of UB-B leads to snow-blindness, also known as arc eye or photokeratitis.

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Sub Category: Class 12 Biology Mcqs

100
Q:

What does the continuous depletion of ozone lead to?

A) Proper rains B) Ozone formation
C) Ozone hole D) Good yield
 
Answer & Explanation Answer: C) Ozone hole

Explanation: Due to the continuous degradation of ozone, the depletion of ozone occurs. This thinning in the layer of ozone is known as the ozone hole.

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84
Q:

In which region is the depletion of ozone particularly marked?

A) Equatorial region B) Temperate region
C) Tropical region D) Antarctic region
 
Answer & Explanation Answer: D) Antarctic region

Explanation: The stratosphere found in the upper layer of the atmosphere has good ozone. This layer acts as a shield and absorbs the harmful, injurious ultraviolet (UV) radiations from the sun. In the Antarctic region, the depletion of ozone particularly marked.

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35
Q:

Who enhances the degradation of ozone?

A) Hydrogen B) Chlorofluorocarbons
C) Oxygen D) Water vapors
 
Answer & Explanation Answer: B) Chlorofluorocarbons

Explanation: Chlorofluorocarbons (CFCs) enhances the degradation of ozone by disturbing the cycle of ozone formation. CFCs upon entering in stratosphere react with UV and release chlorine ions. These ions act as catalysts and degrade ozone releasing molecular oxygen.

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Sub Category: Class 12 Biology Mcqs

33
Q:

How is the thickness of the ozone in a column of air from the ground to the top of the atmosphere measured?

A) Dobson units B) Hertz
C) Centimeter D) Ampere
 
Answer & Explanation Answer: A) Dobson units

Explanation: Dobson unit (DU) is used to measure the thickness of the ozone in a column of air from the ground to the top of the atmosphere. A layer of pure ozone that is 0.01 mm thick at standard temperature and pressure is equivalent to one Dobson unit.

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94
Q:

In which part of the atmosphere is the good ozone found?

A) Ionosphere B) Stratosphere
C) Lithosphere D) Hydrosphere
 
Answer & Explanation Answer: B) Stratosphere

Explanation: The stratosphere found in the upper layer of the atmosphere has good ozone. This layer acts as a shield and absorbs the harmful, injurious ultraviolet (UV) radiations from the sun.

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Sub Category: Class 12 Biology Mcqs

22
Q:

Which one of the following ways can be used to control global warming?

A) Increasing the growth of human population B) Planting trees
C) Increasing the use of fossil fuel D) Increasing deforestation
 
Answer & Explanation Answer: B) Planting trees

Explanation: The increase in temperature of Earth due to an increase in the level of greenhouse gases is known as global warming. This leads to various changes in the environment. This can be controlled by planting trees and afforestation.

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Sub Category: Class 12 Biology Mcqs

34
Q:

Which one of the following ways can be used to control global warming?

A) Increasing deforestation B) Reducing efficiency of energy usage
C) Reducing the use of fossil fuel D) Increasing the growth of human population
 
Answer & Explanation Answer: C) Reducing the use of fossil fuel

Explanation: The phenomenon occurring due to an increase in the level of greenhouse gases is known as global warming. This leads to an increase in Earth’s temperature and leading to deleterious changes in the environment. This can be controlled by reducing the use of fossil fuels.

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