Question Text
Question 1 :
Nitrogen fixation is inhibited by oxygen. However, in aerobic nitrogen-fixing bacteria, nitrogen is fixed in the presence of oxygen. Nitrogenase in such organisms is protected by which one of the following mechanisms.
Question 2 :
All of the following statements concerning the actinomycetous filamentous soil bacterium <i>Frankia</i> are correct except that <i>Frankia</i>
Question 3 :
Metallic mineral that is used in both alloy steels and disinfectants is<br>
Question 4 :
Assertion: Ozone is destroyed by solar radiation in upper stratosphere.
Reason: Thinning of the ozone layer allows excessive UV radiations to reach the surface of earth.
Question 6 :
$CFCl_3$ is responsible for the decomposition of ozone. Which of the following reacts with ozone to form oxygen?
Question 7 :
Assertion: Earth is protected from IR radiations by ozone layer.
Reason: Ozone layer is present in troposphere of the atmosphere.
Question 8 :
In 2012, the UN conference of Parties on climate change was held at
Question 9 :
Air contains $79$% ${N}_{2}$ and ${21}$% ${O}_{2}$ by volume. If the barometric pressure is $750mm$ $Hg$ the partial pressure of oxygen is:<br>($d{N}_{2}=1.25, d{O}_{2}=1.42g/m$)
Question 12 :
Arrange the following in the descending order of their role in soil erosion<br/>(I) Wind erosion<br/>(ii) Chemical degradation<br/>(iii) Physical degradation<br/>(iv) Water erosion<br/>
Question 15 :
Which of the following is responsible for the depletion of the ozone layer in the upper stratosphere of the atmosphere?