Tag: global environmental change

Questions Related to global environmental change

Identify the wrong statement with reference to UV rays.

commercial applications global environmental change causes of resource depletion causes of greenhouse effect ozone layer depletion

  1. UV-A is more harmful to animals than UV-B.

  2. UV radiation falls in the range between 100-300 nm wavelength.

  3. UV radiation is classified into three categories.

  4. UV radiation kills microorganisms.

Show answer
Correct Option: A
Explanation:

  •  The UV region covers the wavelength range 100-400 nm and is divided into three bands: UVA (315-400 nm) UVB (280-315 nm)
  • The most common form of UV radiation is sunlight, which produces three main types of UV rays: UVA, UVB, UVC.
  • At certain wavelengths, UV is mutagenic to bacteria, viruses and other microorganisms. Particularly at wavelengths around 260–270 nm, UV breaks molecular bonds within microorganismal DNA, producing thymine dimers that can kill or disable the organisms.
  • UVB, the chief cause of skin reddening and sunburn, tends to damage the skin's more superficial epidermal layers. It plays a key role in the development of skin cancer and a contributory role in tanning and photoaging.

So, the correct answer is 'UV-A is more harmful to animals than UV-B.'.

Snow blindness is cause due to

commercial applications global environmental change causes of resource depletion causes of greenhouse effect ozone layer depletion

  1. Ozone hole

  2. Nuclear winter

  3. Acid rain

  4. Green house effect

Show answer
Correct Option: A
Explanation:

Cataracts and blindness are among the most common eye diseases associated with further ozone layer depletion and increased UV-B at the Earth's surface.  A 1% decrease in stratospheric ozone may result in 100,000 to 150,000 additional cases of blindness due to eye cataracts worldwide. The ozone layer is responsible for absorbing harmful ultraviolet rays, and preventing them from entering the Earth's atmosphere.

So the correct answer is 'Ozone hole'.

Which of the following statement/s is/are correct with regard to ozone depletion:
1. The ozone hole is measured in terms of ozone concentrations, which is expressed in Dobson units.
2. The major cause for ozone depletion is the presence of CFCs in the stratosphere - CFCs are entirely man-made and not found naturally.

commercial applications global environmental change causes of resource depletion causes of greenhouse effect ozone layer depletion

  1. Only 1

  2. Only 2

  3. Both A and B

  4. None of the above

Show answer
Correct Option: C
Explanation:

  • CFCs and other halogenated ozone depleting substances (ODS) are mainly responsible for manmade chemical ozone depletion.
  • The total amount of effective halogen (Chlorine and bromine) in the stratosphere can be calculated and are known as the equivalent effective stratospheric chlorine.
So, the correct option is 'Both A and B'.

Ozonosphere occurs at height of

commercial applications global environmental change causes of resource depletion causes of greenhouse effect ozone layer depletion

  1. 8-10 km. above poles

  2. 8-10 km. above equator

  3. 11-16 km above poles

  4. 11=-16 km above equator

Show answer
Correct Option: C

High concentration of greenhouse gases has resulted in maximum rise of atmospheric temperature in 

biology global environmental change causes of greenhouse effect greenhouse effect pollution and its effects

  1. Tropic region

  2. Middle latitude

  3. Polar region

  4. Temperate region

Show answer
Correct Option: C
Explanation:
Increases in the level of greenhouse gases has led to considerable heating of earth leading to global warming. During the past century, the temperature of earth has increased by $ 0.6  $, most of it during the last three decades. Rise in temperature is slight in tropics, moderate in middle latitudes and maximum in polar regions. It will led to melting of polar ice caps as well as of other places like the Himalayan snow caps.
So, the correct answer is 'Polar region'.

If there is no greenhouse effect, then the average temperature at surface of earth would have been 

biology global environmental change causes of greenhouse effect greenhouse effect pollution and its effects

  1. $ 15 $

  2. $ -18 $

  3. $ -6 $

  4. $ 10 $

Show answer
Correct Option: B
Explanation:
Greenhouse gases like $ { CO } _{ 2 }, { CH }{ 4 } $ and $ { CFC } _{ s } $ are essential for keeping the earth warm and hospitable. They prevent a substantial part of long wave radiations emitted by earth to escape into space, but these gases radiate a part of this energy back to the earth. This phenomenon is called greenhouse effect. Because of green house effect, the mean annual temperature of earth is $ 15. $ In its absence, it will fall to $ -18. $
So, the correct answer is '$ -18. $'

Which of the following is correct regarding 'El Nino' effect?

biology global environmental change causes of greenhouse effect greenhouse effect pollution and its effects

  1. Temperature rise leads to odd climatic changes

  2. Cutting down the use of fossil fuels

  3. Planting more trees

  4. Slowing down the growth of human population

Show answer
Correct Option: A
Explanation:
The rise in temperature due to global warming is leading to deleterious changes in the environment and resulting in odd climatic changes like EL Nino effect. El Nino effect is the abnormal warming of surface ocean water. It affects the weather in large parts of the world. Moisture carrying capacity of air will increase. Pattern of air-mass movement will change. Precipitation will increase at higher latitudes both in summer and winter and in southern as well as Eastern Asia in summer. Frequency of droughts and floods  will increase. Threat to human health will increase in tropical and subtropical countries due to changed ranges of disease vectors and water borne pathogens.
So, the correct answer is 'Temperature rise leads to odd climatic changes'.

Denitrification is caused by

zoology global environmental change causes of greenhouse effect greenhouse effect pollution and its effects

  1. Pseudomonas

  2. Nitrobacter

  3. Nitrosomonas

  4. Azotobacter

Show answer
Correct Option: A
Explanation:
Denitrification is the process of degradation of fixed nitrogenous compounds to free nitrogen which is released back to the atmosphere. It is performed by several bacteria like Pseudomonas which utilize nitrate to form nitrite in a process called reduction. Nitrite is further reduced to nitric oxide then to nitrous oxide and then nitrogen gas. This process reduces the fertility and ultimately the agricultural productivity decreases.
Thus, the correct answer is option A.

Warm ocean surge of Peru current recurring every 5-8 years or so in the East Pacific of South America is widely known as.

biology global environmental change causes of greenhouse effect greenhouse effect pollution and its effects

  1. Gulf Stream

  2. Aye Aye

  3. El Nino

  4. Mangox

Show answer
Correct Option: C
Explanation:

EI Nino describes the unusual warming of surface waters in the eastern tropical pacific ocean. This occurs when the normal trade winds weaken or get reverse which lets the warm water flow in the eastern Pacific instead towards the west. Thus it forms oscillation in the ocean-atmosphere.

So,the correct answer is option C.

Which of the following cause green house effect?
(i) Deforestation
(ii) Emission of gases from factories
(iii) Melting of polar ice

biology global environmental change causes of greenhouse effect greenhouse effect pollution and its effects

  1. Only (i) and (ii)

  2. Only (i) and (iii)

  3. Only (ii) and (ii)

  4. (i), (ii) and (iii)

Show answer
Correct Option: A
Explanation:
Deforestation is removal, decrease or deterioration of forest cover of an area. It causes the change in climate, floods, soil erosion, siltation, cyclones, drought, desertification and increased level of carbon dioxide (greenhouse gas) in the atmosphere. Greenhouse gases like carbon dioxide and CH$ _4$ that are also released from factories cause green house effect.