Tag: zoology

Quizzes (289) Questions (5869)

Questions Related to zoology

Multiple choice zoology allotropy of oxygen ozone - a case study stratospheric pollution ozone and its depletion

In Antarctica ozone depletion is due to the formation of following compound.

  1. Acroline

  2. Chlorine nitrate

  3. Formyldehyde
  4. $SO _3$ and $SO _2$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The severe depletion of the Antarctic ozone layer known as the ozone hole occurs because of the special atmospheric and chemical conditions that exist there and nowhere else on the globe. The very low winter temperatures in the Antarctic stratosphere cause polar stratospheric clouds (PSCs) to form. These clouds contain Chlorine nitrate $(ClNO _3)$

Option (B) is correct.

Multiple choice zoology natural resources- air, water and land ozone - a case study stratospheric pollution ozone and its depletion

A considerable part of the harmful ultraviolet radiation of the Sun does not reach the surface due to:

  1. $CO _2$
  2. $N _2$
  3. $O _3$
  4. $O _2$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ozone is formed as a result of the action of U.V. light on oxygen and it forms a layer in upper layers of the atmosphere. 


It protects life on earth from harmful U.V. radiation.

So, the correct option is $A$

Multiple choice zoology natural resources- air, water and land ozone - a case study stratospheric pollution ozone and its depletion

What would happen, if all the oxygen present in the environment is converted to ozone?

  1. We will be protected more.

  2. It will become poisonous and kill living forms.

  3. Ozone is not stable, hence it will be toxic.

  4. It will help harmful sun radiations to reach earth and damage many life forms
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ozone is a form of elemental oxygen. In its most stable form, elemental oxygen exists as diatomic molecules (O2). The molecules of ozone contain three oxygen atoms (O3) and are unstable with respect to O2. Ozone is a very reactive gas, and even at low concentrations it is irritating and toxic. It occurs naturally in small amounts in the Earth's upper atmosphere, and in the air of the lower atmosphere after a lightning storm. 

Ozone has been implicated to have an adverse effect on plant growth: "... ozone reduced total chlorophylls, carotenoid and carbohydrate concentration, and increased 1-aminocyclopropane-1-carboxylic acid (ACC) content and ethylene production. In treated plants, the ascorbate leaf pool was decreased, while lipid peroxidation and solute leakage were significantly higher than in ozone-free controls. 

Ozone, along with reactive forms of oxygen such as superoxide, singlet oxygen, hydrogen peroxide superoxide, singlet oxygen, hydrogen peroxide, and hypochlorite ions, is naturally produced by white blood cells and other biological systems (such as the roots of marigolds) as a means of destroying foreign bodies. 

Thus Option B is correct.

Multiple choice zoology natural resources- air, water and land ozone - a case study stratospheric pollution ozone and its depletion

Biological importance of ozone layer is :

  1. ozone layer stops ultraviolet rays

  2. ozone layer reduces green house effect

  3. ozone layer reflects radio waves
  4. ozone layer controls $O _2/H _2$ radio in atmosphere
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ozone is an allotropic form of oxygen. 

It is too reactive to remain for long in the atmosphere at sea level.
At a height of about 20 kilometres, it is forrmed from the atmospheric oxygen in the presence of sunlight.
This layer protects us from the excessive concentration of U.V radiation.

Multiple choice zoology natural resources- air, water and land ozone - a case study stratospheric pollution ozone and its depletion

A considerable part of harmful ultraviolet radiation from the sun does not reach the surface of the earth. This is because high above the earth's atmosphere is a layer of_________

  1. Carbon dioxide

  2. Hydrogen

  3. Ozone

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

The presence of the layer of ozone prevents the UV rays from reaching the surface of the earth.


The reactions that occur are shown below:
$O _{3}\overset{h\nu}{\rightarrow} O _{2} + [O]$
$2O _{3}\overset{h\nu}{\rightarrow} 3O _{2}$

Option C is correct.