Environmental Studies · Geography

Atmospheric Structure and Ozone

1,319 Questions

Atmospheric structure and ozone layer topics examine the Earth's atmospheric layers, the impact of solar radiation, and ozone depletion mechanisms. These environmental science concepts are crucial for general awareness sections in multiple competitive examinations. Review these questions to solidify your understanding of the stratosphere, polar vortex effects, and greenhouse gases.

Earth's atmospheric layersOzone layer depletionSolar ultraviolet radiationPolar vortex effectsCarbon dioxide impactOzone-depleting substances

Atmospheric Structure and Ozone Questions

Multiple choice

Ozone layer protects us from __________.

  1. air pollution

  2. sun's harmful rays

  3. solar heat

  4. sudden climatic changes
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The ozone layer in the stratosphere absorbs harmful ultraviolet (UV) radiation from the sun, preventing it from reaching Earth's surface. This UV protection is crucial for living organisms as excessive UV radiation can cause skin cancer and damage ecosystems. The ozone layer does not protect against air pollution, solar heat, or sudden climatic changes.

Multiple choice

Which compound is considered to be responsible for the depletion of the ozone layer?

  1. Chlorofluorocarbons

  2. Oxides

  3. Sulphides

  4. Hydroxides
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Chlorofluorocarbons (CFCs) are synthetic compounds that break down in the stratosphere and release chlorine atoms, which catalytically destroy ozone molecules. This depletion of the ozone layer allows more harmful UV radiation to reach Earth. Oxides, sulphides, and hydroxides are not responsible for ozone depletion.

Multiple choice

A recent hole in the ozone layer has been found above ________.

  1. Australia

  2. Asia

  3. Europe

  4. Antarctica

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The ozone hole is primarily located over Antarctica due to extreme cold temperatures and polar vortex dynamics that create ideal conditions for ozone depletion. The Antarctic region experiences the most severe ozone thinning, especially during spring (September-October).

Multiple choice

How are the CFCs responsible for the reduction of ozone layer?

  1. CFC's displace the ozone layer

  2. CFC's absorb the ozone gas

  3. CFC's react with the ozone gas

  4. CFC's cover the ozone layer

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

CFCs (chlorofluorocarbons) react chemically with ozone molecules in the stratosphere, breaking them down. This reaction occurs when UV radiation splits CFC molecules, releasing chlorine atoms that catalytically destroy ozone.

Multiple choice

What would be the immediate effect of depletion of ozone layer?

  1. Most of the sun's rays will be reflected back.

  2. The harmful sun's rays will reach the earth's surface.

  3. The temperature of the earth will increase.

  4. The concentration of chlorofluorocarbons will increase in the atmosphere.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The ozone layer absorbs harmful UV-B radiation from the sun. When ozone is depleted, more UV rays reach Earth's surface, increasing risks of skin cancer, cataracts, and ecosystem damage. Temperature effects are secondary and indirect.

Multiple choice

The ozone protects the earth from the ____________ of the sun.

  1. U.V. rays

  2. X rays

  3. gamma rays

  4. infra red rays
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The ozone layer in the stratosphere absorbs most of the sun's harmful ultraviolet (UV) radiation, preventing it from reaching Earth's surface. This protection is crucial for preventing skin cancer and protecting ecosystems.

Multiple choice

Which of the following is known as the real ozone killer?

Directions: Read the following passage carefully and answer the questions by selecting the most appropriate options.

We are today faced with a great ecological problem for which we ourselves are largely responsible. Our planet, the Earth, the only home of man is bathed in a steady rain of the sun's rays. Most of these rays supply us heat and light, but a small percentage is deadly. These are the ultraviolet - B rays (or UV - B). If these were to get to the surface of the Earth directly, they would kill us off. Luckily, the Earth’s surface is shielded from these rays by the ozone layer; but sadly enough this ozone layer is being destroyed by man.
The ozone layer is formed from a kind of oxygen with three atoms (O3) instead of the normal two (O2). Ozone oc­curs naturally in the stratosphere, several kilometres above the Earth's surface. It absorbs the dangerous UV -B rays but allows the much needed and safe light to pass through. There, in the stratosphere, it is constantly being created by the sun's rays; thus it is a self-repairing shield. But man is now gradu­ally destroying this vital shield with his industrial gases. The most lethal of these gases are the chlorofluorocarbons, or CFCs, which are used in making all kinds of foamed plastic products, propellants in spray cans, coolants in air condi­tioners and refrigerators and solvents to clean electronic equip­ment.

Down here, they are not lethal. But after they have leaked from air conditioners, plastic foam, cups, etc.; they slowly drift up to the stratosphere where, bombarded by ultraviolet rays, they break up at last, releasing chlorine, the real ozone killer. Sadly, one chlorine molecule may remain active for a century, destroying thousands of ozone molecules.

 

  1. Refrigerators & air conditioners

  2. Chlorofluorocarbons

  3. Chlorine

  4. Propellants
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The passage explicitly states: 'they break up at last, releasing chlorine, the real ozone killer.' Chlorine is identified as the actual ozone-destroying agent, while CFCs are the source that releases chlorine in the stratosphere.

Multiple choice

Which of the following statements best describes the ozone layer?

Directions: Read the following passage carefully and answer the questions by selecting the most appropriate options.

We are today faced with a great ecological problem for which we ourselves are largely responsible. Our planet, the Earth, the only home of man is bathed in a steady rain of the sun's rays. Most of these rays supply us heat and light, but a small percentage is deadly. These are the ultraviolet - B rays (or UV - B). If these were to get to the surface of the Earth directly, they would kill us off. Luckily, the Earth’s surface is shielded from these rays by the ozone layer; but sadly enough this ozone layer is being destroyed by man.
The ozone layer is formed from a kind of oxygen with three atoms (O3) instead of the normal two (O2). Ozone oc­curs naturally in the stratosphere, several kilometres above the Earth's surface. It absorbs the dangerous UV -B rays but allows the much needed and safe light to pass through. There, in the stratosphere, it is constantly being created by the sun's rays; thus it is a self-repairing shield. But man is now gradu­ally destroying this vital shield with his industrial gases. The most lethal of these gases are the chlorofluorocarbons, or CFCs, which are used in making all kinds of foamed plastic products, propellants in spray cans, coolants in air condi­tioners and refrigerators and solvents to clean electronic equip­ment.

Down here, they are not lethal. But after they have leaked from air conditioners, plastic foam, cups, etc.; they slowly drift up to the stratosphere where, bombarded by ultraviolet rays, they break up at last, releasing chlorine, the real ozone killer. Sadly, one chlorine molecule may remain active for a century, destroying thousands of ozone molecules.

 

  1. It stops the UV Rays from reaching the earth's surface.

  2. It absorbs the UV rays and allows the much needed safe light to pass through.

  3. It contains deadly gases.

  4. It is made up of Oxygen and CFC molecules
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The passage states the ozone layer 'absorbs the dangerous UV-B rays but allows the much needed and safe light to pass through.' This accurately describes its dual function as a selective filter.

Multiple choice

The ozone layer is

Directions: Read the following passage carefully and answer the questions by selecting the most appropriate options.

We are today faced with a great ecological problem for which we ourselves are largely responsible. Our planet, the Earth, the only home of man is bathed in a steady rain of the sun's rays. Most of these rays supply us heat and light, but a small percentage is deadly. These are the ultraviolet - B rays (or UV - B). If these were to get to the surface of the Earth directly, they would kill us off. Luckily, the Earth’s surface is shielded from these rays by the ozone layer; but sadly enough this ozone layer is being destroyed by man.
The ozone layer is formed from a kind of oxygen with three atoms (O3) instead of the normal two (O2). Ozone oc­curs naturally in the stratosphere, several kilometres above the Earth's surface. It absorbs the dangerous UV -B rays but allows the much needed and safe light to pass through. There, in the stratosphere, it is constantly being created by the sun's rays; thus it is a self-repairing shield. But man is now gradu­ally destroying this vital shield with his industrial gases. The most lethal of these gases are the chlorofluorocarbons, or CFCs, which are used in making all kinds of foamed plastic products, propellants in spray cans, coolants in air condi­tioners and refrigerators and solvents to clean electronic equip­ment.

Down here, they are not lethal. But after they have leaked from air conditioners, plastic foam, cups, etc.; they slowly drift up to the stratosphere where, bombarded by ultraviolet rays, they break up at last, releasing chlorine, the real ozone killer. Sadly, one chlorine molecule may remain active for a century, destroying thousands of ozone molecules.

 

  1. a man-made shield located in the stratosphere

  2. a naturally occurring shield in the stratosphere

  3. a shield made of various industrial gases

  4. a shield formed as a result of heavy rains
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The passage clearly states: 'Ozone occurs naturally in the stratosphere, several kilometres above the Earth's surface' and describes it as a 'self-repairing shield' constantly being created by the sun's rays, confirming it's natural, not man-made.

Multiple choice

The greatest threat to the ozone layer is from

Directions: Read the following passage carefully and answer the questions by selecting the most appropriate options.

We are today faced with a great ecological problem for which we ourselves are largely responsible. Our planet, the Earth, the only home of man is bathed in a steady rain of the sun's rays. Most of these rays supply us heat and light, but a small percentage is deadly. These are the ultraviolet - B rays (or UV - B). If these were to get to the surface of the Earth directly, they would kill us off. Luckily, the Earth’s surface is shielded from these rays by the ozone layer; but sadly enough this ozone layer is being destroyed by man.
The ozone layer is formed from a kind of oxygen with three atoms (O3) instead of the normal two (O2). Ozone oc­curs naturally in the stratosphere, several kilometres above the Earth's surface. It absorbs the dangerous UV -B rays but allows the much needed and safe light to pass through. There, in the stratosphere, it is constantly being created by the sun's rays; thus it is a self-repairing shield. But man is now gradu­ally destroying this vital shield with his industrial gases. The most lethal of these gases are the chlorofluorocarbons, or CFCs, which are used in making all kinds of foamed plastic products, propellants in spray cans, coolants in air condi­tioners and refrigerators and solvents to clean electronic equip­ment.

Down here, they are not lethal. But after they have leaked from air conditioners, plastic foam, cups, etc.; they slowly drift up to the stratosphere where, bombarded by ultraviolet rays, they break up at last, releasing chlorine, the real ozone killer. Sadly, one chlorine molecule may remain active for a century, destroying thousands of ozone molecules.

 

  1. chlorofluorocarbons

  2. UV - B Rays

  3. O3 molecules

  4. foamed plastic products
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The passage states CFCs are 'the most lethal of these gases' used in various industrial products, and that they 'drift up to the stratosphere' where they 'break up at last, releasing chlorine.' While chlorine does the damage, CFCs are the greatest threat because they're the source that delivers chlorine to the stratosphere.

Multiple choice

Which word in the passage is a synonym of 'deadly'?

Directions: Read the following passage carefully and answer the questions by selecting the most appropriate options.

We are today faced with a great ecological problem for which we ourselves are largely responsible. Our planet, the Earth, the only home of man is bathed in a steady rain of the sun's rays. Most of these rays supply us heat and light, but a small percentage is deadly. These are the ultraviolet - B rays (or UV - B). If these were to get to the surface of the Earth directly, they would kill us off. Luckily, the Earth’s surface is shielded from these rays by the ozone layer; but sadly enough this ozone layer is being destroyed by man.
The ozone layer is formed from a kind of oxygen with three atoms (O3) instead of the normal two (O2). Ozone oc­curs naturally in the stratosphere, several kilometres above the Earth's surface. It absorbs the dangerous UV -B rays but allows the much needed and safe light to pass through. There, in the stratosphere, it is constantly being created by the sun's rays; thus it is a self-repairing shield. But man is now gradu­ally destroying this vital shield with his industrial gases. The most lethal of these gases are the chlorofluorocarbons, or CFCs, which are used in making all kinds of foamed plastic products, propellants in spray cans, coolants in air condi­tioners and refrigerators and solvents to clean electronic equip­ment.

Down here, they are not lethal. But after they have leaked from air conditioners, plastic foam, cups, etc.; they slowly drift up to the stratosphere where, bombarded by ultraviolet rays, they break up at last, releasing chlorine, the real ozone killer. Sadly, one chlorine molecule may remain active for a century, destroying thousands of ozone molecules.

 

  1. shielded

  2. lethal

  3. vital

  4. active
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The passage states that 'a small percentage is deadly' referring to UV-B rays. Later it describes chlorofluorocarbons as 'the most lethal of these gases.' Since 'lethal' and 'deadly' both mean causing death, they are synonyms. The other options (shielded, vital, active) describe different qualities of the ozone layer or chlorine but do not mean deadly.

Multiple choice

In the beginning there was no oxygen in atmosphere. The activity of which organism is supposed to have made the earth's atmosphere aerobic or oxygen-rich?

  1. Monocotyledons

  2. Filamentous algae

  3. Cyanobacteria

  4. Mycoplasma

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Cyanobacteria (blue-green algae) were the first organisms to perform oxygenic photosynthesis, gradually converting Earth's reducing atmosphere to an oxygen-rich one over billions of years. Monocotyledons are plants that evolved much later, while filamentous algae and mycoplasma do not produce oxygen through photosynthesis.

Multiple choice

With the help of which phenomenon does carbon dioxide keep the earth’s atmosphere warm?

  1. Photosynthesis

  2. Respiration

  3. Breathing

  4. Greenhouse effect

  5. Water cycle
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Global warming is the rise in the average temperature of earth's atmosphere and oceans. Warming of the climate system is primarily caused by increasing concentrations of greenhouse gases produced by human activities such as the burning of fossil fuels and deforestation. The heat caused by infrared radiation is absorbed by greenhouse gases such as water vapour, carbon dioxide, ozone and methane which slow its escape from the atmosphere. Although greenhouse gases make up only about 1 percent of the earth's atmosphere, they regulate our climate by trapping heat and holding it in a kind of warm air blanket that surrounds the planet. This phenomenon is what scientists call the greenhouse effect. Without it, scientists estimate that the average temperature on earth would be colder by approximately 30 degrees, far too cold to sustain our current ecosystem.