NCERT Books Free Download for Class 12 Biology Chapter 16 - Environmental Issues

All over the country, CBSE candidates are prescribed NCERT books to help them grasp the entirety of the subject as easily as possible. Students of Class 12, those who have taken up the Science stream are usually worried about how to juggle the various subjects that they have taken up. During this time, NCERT comes to the rescue of the students as the contents are explained in a much lucid and comprehensible way. 

The exercises at the end of the chapters prove beneficial for regular practice as well as to check the progress of a candidate. Biology as a subject needs illustrations along with the content to make the topics much more interesting. This is clearly visible in the book as diagrams are illustrated in relation to the content for better understanding. The contents of the class 12 Biology prescribed in the CBSE syllabus are as follows:

• Reproduction

• Genetics and Evolution

• Biology in Human Welfare

• Biotechnology

• Ecology

To get a clear idea on the topics above, students can download the Vedantu app available online, download the PDF and access it at their own disposal. Students can also visit the official website of NCERT and through the list of subjects available, they can click on the required subject and the topic and easily find it accessible. 

Under the unit Ecology, students can find the chapter “environmental issues” which specifically discusses all the environmental concerns and tries to find out means to improve the same. The major topic handled is Environmental pollution and how global warming is becoming a serious issue for the same. Some of the detailed analyses of the topic are discussed below:

Environmental Pollution

Pollution is an undesirable change caused to the chemical, biological, and physical composition of air, soil, and water. The wastes that cause pollution are called pollutants. The various pollution types include air, water, noise, soil, and radioactive pollution.

Understanding Global Warming

Global warming is the gradual increase in the temperature of the Earth. It happens when there is an increase in the level of greenhouse gases in the atmosphere. The greenhouse gases present in the atmosphere prevent heat captured from the sun from escaping to outer space. These gases are thus responsible for keeping the Earth warm. With the rise in the level of greenhouse gases, the Earth’s temperature also rises. This is an environmental concern that can cause problems to nature and, eventually, to humans. Global warming is caused because of industrialization, deforestation, vehicle emission, and farming in factories.

Solid Waste

Solid waste comes from offices, homes, hospitals, and schools that are disposed of by the town municipality. These comprise solid wastes like plastics, paper, glass, leather, and many more such things. Solid waste is either dumped or burnt in the sanitary landfill.

Depletion of Natural Resources

When the natural resources get depleted, then this too causes environmental pollution. The consumption of fossil fuels leads to the emission of greenhouse gas. This again causes a change in the climate and leads to global warming.

Electronic Wastes

Electronic wastes are basically electronic goods like computers that are unrepaired. These are called e-wastes, which are either buried in the landfills, or they are incinerated. The e-wastes that are generated in the developed countries are sent to the developing nations to recover metals like iron, copper, gold, nickel, etc. Recycling is the only way to treat the e-wastes, but care should be taken to carry out recycling in an environmentally friendly way.

Agro - Chemicals

Inorganic pesticides and fertilizers have seen a massive increase in use because of the green revolution. This helps to enhance the production of crops. The insecticides and pesticides are toxic, and these target the organisms in the ecosystem of the soil. These get biomagnified in the terrestrial ecosystem that causes eutrophication in the ecosystem of aquatic life.

Deforestation

Another major environmental concern is deforestation. This happens because of the destruction of trees that are used to make buildings. Trees are also cut for obtaining raw materials. Deforestation causes global warming, soil erosion, and also leads to extinction in biodiversity.

Others

Loss in biodiversity, depletion of the ozone layer, effects on marine life and increase in the carbon footprint are other factors that cause environmental issues.

All these topics can be handled separately by downloading the PDF from the Vedantu site, its official site and students can also get the solutions handy through the same site. Vedantu tries to make the learning process much easier for candidates and thus, make it an enriching experience for them.