Why ozone hole forms over Antarctica? Ho | Class 12 Biology Chapter Environmental Issues, Environmental Issues NCERT Solutions

Welcome to the NCERT Solutions for Class 12 Biology - Chapter Environmental Issues. This page offers a step-by-step solution to the specific question from Exercise 1, Question 6: . With detailed answers and explanations for each chapter, students can strengthen their understanding and prepare confidently for exams. Ideal for CBSE and other board students, this resource will simplify your study experience.

Question 6: Why ozone hole forms over Antarctica? How will enhanced ultraviolet Radiations affect us?
Answer:

The ozone hole is more prominent over the region of Antarctica. It is formed due to an increased concentration of chlorine in the atmosphere.

Chlorine is mainly released from chlorofluorocarbons (CFC’s) widely used as refrigerants. The CFC’s magnate from the troposphere to the stratosphere, where they release chlorine atoms by the action of UV rays on them. The release of Chlorine atoms causes the conversion of ozone into molecular oxygen. One atom of chlorine can destroy around 10,000 molecules of ozone and causes ozone depletion.

The formation of the ozone hole will result in an increased concentration of UV - B radiations on the Earth’s surface. UV −B damages DNA and activates the process of skin ageing. It also causes skin darkening and skin cancer. High levels of UV −B cause corneal cataract in human beings.


Study Tips for Answering NCERT Questions:

NCERT questions are designed to test your understanding of the concepts and theories discussed in the chapter. Here are some tips to help you answer NCERT questions effectively:

  • Read the question carefully and focus on the core concept being asked.
  • Reference examples and data from the chapter when answering questions about Environmental Issues.
  • Review previous year question papers to get an idea of how such questions may be framed in exams.
  • Practice answering questions within the time limit to improve your speed and accuracy.
  • Discuss your answers with your teachers or peers to get feedback and improve your understanding.

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Comments

  • Arunachal
  • May 02, 2019

Suraj singh really


  • suraj singh
  • Jan 28, 2017

ok you are right there is high concentration of chlorine in atmosphere of antartica but the reason of this high conc. are stratospheric clouds which formed during colder weather in antartica these clouds enhance the catalytic role of Chloride in stratosphere.


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Welcome to the NCERT Solutions for Class 12 Biology - Chapter . This page offers a step-by-step solution to the specific question from Excercise 1 , Question 6: Why ozone hole forms over Antarctica? How will enhanced ultraviolet Radiations affect us?....