NCERT Solutions for Class 12 Biology, Chapter 16 - Environmental Issues

This chapter is the study of issues that arise in the environment. Pollution is one of the reasons behind the problems that we face in our environment today. Various kinds of pollutants have been explained in this chapter, thoroughly. It also discusses how these pollutants that are destroying the environment can be controlled.

Let us look at the contents of Class 12 Biology Chapter 16, Environmental Issues

16.1 Air Pollution and Its Control

16.2 Water Pollution and Its Control

16.3 Solid Wastes

16.4 Agrochemicals and their Effects

16.5 Radioactive Wastes

16.6 Greenhouse Effect and Global Warming

16.7 Ozone Depletion in the Stratosphere

16.8 Degradation by Improper Resource, Utilisation and Maintenance

16.9 Deforestation

In this chapter, you will study:

Section 16.1: In this section, you will learn the factors which cause pollution in the air and the measures one can take up to control them. Pollutants in the air cause harm to all living organisms. It reduces the growth of crops and also becomes a reason for their premature death. They are also harmful to the respiratory system of human beings and animals. For more information, you may refer to NCERT Solutions for Class 12 Biology Chapter 16, here at UrbanPro. Here, a case study on controlling vehicular air pollution in New Delhi has also been discussed.

Section 16.2: Water pollution is the pollution which is caused by human beings by releasing all kinds of waste into water bodies. In this section, you will learn about how human beings pollute water and how you can help to control it. In this section, the effects of domestic sewage and industrial effluents have been explained and a case study of integrated wastewater treatment has also been discussed here.

Section 16.3: In this section, solid waste is explained to you. It is the waste that goes to the trash such as municipal solid wastes like paper, food wastes, plastics, rubber, metal, leather, etc. Solid wastes can be categorized into three parts; they are biodegradable, recyclable, and non-biodegradable. Case study of remedy for plastic waste has been given in this section.

Section 16.4: In this section of chapter 16, you will learn the effects of agrochemicals. Agrochemicals are chemicals like pesticides, insecticides, and inorganic fertilizers which are used in increasing the production of crops. These agrochemicals are toxic and cause harm to the organic components of the soil. here a  case study of Organic Farming has also been discussed.

Section 16.5: In this section, you will study about radioactive waste and its side effects on the ecosystem. Radioactive waste is the by-product of nuclear power plants which are poisonous for all living organisms.

Section 16.6: In this section, the greenhouse effect refers to the trapping of warmth coming from the sun in the lower atmosphere of a planet. This happens because the atmosphere is transparent to visible radiation that is being emitted from the sun. Global warming refers to the rise in temperature in the climate system of Earth.

Section 16.7: In this section, you will study the depletion of the Ozone layer in the Stratosphere. The Earth is composed of seven atmospheres, and the stratosphere is one of them. The ozone layer of the Earth protects all living organisms from the harmful radiation of the sun. However, it is due to human activity that the ozone layer is depleting and is unable to protect the ecosystem from the UV rays. You may refer to Chapter 16 Biology Class 12 NCERT Solutions for more information.

Section 16.8: In this section, you will learn about the degradation of natural resources that is caused by being overused by humans. Soil erosion and desertification, grazing and deforestation are some of the ways by which humans are misusing natural resources.

Section 16.9: For the final section, you will study about deforestation and reforestation. These two are discussed in this section thoroughly. A case study of People’s Participation in Conservation of Forests has also been discussed here. Deforestation is the permanent removal of trees in order to make more space for industrial and urban growth; whereas reforestation is the natural process of planting and growing more forests and woodlands.

For a better understanding of this chapter, refer to NCERT Class 12 Biology Chapter 16, here at UrbanPro.