Question

An increase in carbon dioxide content in the atmosphere would not cause

• A. More heat to be retained by the environment
• B. Increase in photosynthesis in plants
• C. Global warming
• D. Abundance of desert plants

Answer 1

Answer: (D)

Abundance of desert plants

Earth surface re-emits heat, obtained from the sun, in the form of infrared radiation but part of this does not escape into space as atmospheric gases (e.g., carbon dioxide, methane, etc.) absorb a major fraction of it. The molecules of these gases radiate heat energy,and a major part of which again comes to Earths surface, thus heating it up once again.This cycle is repeated many times. The gases carbon dioxide, methane, chlorofluorocarbons and nitrous oxide are commonly known as greenhouse gases because they are responsible for the greenhouse effect. The greenhouse effect leads to global warming. Carbon dioxide is also one of the substrates used in the photosynthesis process. An increase in carbon dioxide concentration will increase the rate of photosynthesis. An increase in deserts is called desertification. Desertification will lead to the spread of desert plants. Several factors like a decrease in rainfall, atmospheric pollution, deforestation etc are responsible for the spread of deserts but desertification is not directly linked to increasing carbon dioxide concentration.

So, the correct answer is option D.