NCERT Solutions Class 12 Biology Chapter 16 Environmental Issues

Scroll down for PDF

NCERT Solutions Class 12 Biology Chapter 16 Environmental Issues. The NCERT solutions for Class 11 Mathematics have been made by Mathematics teacher of one of the best CBSE school in India. These NCERT solutions have been made to give detailed answers and expanations of the concepts as per NCERT which can be easily understood by the students. Refer to other links also to download mathematics NCERT solutions, worksheets, sample papers and Exemplar Solutions. 

Class 12 Biology

NCERT Solutions

Chapter 16 Environmental Issues

Question 1: What are the various constituents of domestic sewage? Discuss the effects of sewage discharge on a river.

Answer Domestic sewage is the waste originating from the kitchen, toilet, laundry, and other sources. It contains impurities such as suspended solid (sand, salt, clay), colloidal material (fecal matter, bacteria, plastic and cloth fiber), dissolved materials (nitrate, phosphate, calcium, sodium, ammonia), and disease-causing microbes. When organic wastes from the sewage enter the water bodies, it serves as a food source for micro- organisms such as algae and bacteria. As a result, the population of these micro- organisms in the water body increases. Here, they utilize most of the dissolved oxygen for their metabolism. This results in an increase in the levels of Biological oxygen demand (BOD) in river water and results in the death of aquatic organisms. Also, the nutrients in the water lead to the growth of planktonic algal, causing algal bloom. This causes deterioration of water quality and fish mortality.

Question 2: List all the wastes that you generate, at home, school or during your Trips to other places, could you very easily reduce? Which would be Difficult or rather impossible to reduce?

Answer Wastes generated at home include plastic bags, paper napkin, toiletries, kitchen wastes (such as peelings of vegetables and fruits, tea leaves), domestic sewage, glass, etc. Wastes generated at schools include waste paper, plastics, vegetable and fruit peels, food wrappings, sewage etc. Wastes generated at trips or picnics include plastic, paper, vegetable and fruit peels, disposable cups, plates, spoons etc. Yes, wastes can be easily reduced by the judicious use of the above materials. Wastage of paper can be minimized by writing on both sides of the paper and by using recycled paper. Plastic and glass waste can also be reduced by recycling and re-using. Also, substituting plastics bags with biodegradable jute bags can reduce wastes generated at home, school, or during trips. Domestic sewage can be reduced by optimizing the use of water while bathing, cooking, and other household activities. Non- biodegradable wastes such as plastic, metal, broken glass, etc are difficult to decompose because micro-organisms do not have the ability to decompose them.

Please click the link below to download NCERT Solutions Class 12 Biology Chapter 16 Environmental Issues.

 

Tags: 


Click on the text For more study material for Biology please click here - Biology

Latest NCERT & CBSE News

Read the latest news and announcements from NCERT and CBSE below. Important updates relating to your studies which will help you to keep yourself updated with latest happenings in school level education. Keep yourself updated with all latest news and also read articles from teachers which will help you to improve your studies, increase motivation level and promote faster learning

Registration of NEET 2020 starts

The NEET 2020 registration process would start on Monday, December 2nd, 2019. National Testing Agency, NTA would carry out the county’s undergraduate entrance exam for medical and dental admissions.  The examination is scheduled to take place in English, Hindi, and...

CBSE and Microsoft join hands to build capacity for AI learning for schools

Central Board of Secondary Education and Microsoft join hands to build capacity for AI learning for schools : The officials from the Central Board of Secondary Education have announced that they have partnered with Microsoft India to conduct several capacity building...

Seven Motivational tips for every student

If you’re are a student or a learner and you doesn’t feel like study then this article is going to be very important for you, Reading constantly and Staying motivated as a student is one of the most challenging tasks and barriers to educational success. Education is...

CBSE Circular Aryabhatta Ganit Challenge

For students with a keen interest in mathematics are now provided with a better opportunity to explore their knowledge. CBSE has announced to conduct an exam for the purpose of generating interest in maths among students. It is a trial to clarify the myth that...

CBSE examination board hike the fee for class 10th and 12th

The CBSE (Central Board Secondary Education) increased the examination fees for classes 10 and 12 of the 2020 boards, with no profit no loss principle, from Rs. 750 to Rs 1500, for all categories of students, including SC/ST candidates for all schools throughout India...

Extension of dates by CBSE for Single Girl Child Merit (SGC) scholarship

CBSE has announced to extend dates for SGC scholarship. Previously the dates to submit the SGC scholarship form were 18 October 2019. Now dates have shifted. For online submission, the last date is 31st October. Whereas date for submission of hard copies of renewal...

×
Studies Today