Download Lakhmir Singh Solutions for Class 7 Science Chapter 18 Wastewater Story Free PDF






FAQs on Lakhmir Singh Solutions for Class 7 Science Chapter 18 Wastewater Story - PDF
1. What are contaminants?
The impurities in water that cause contamination are called contaminants.
Example: Byproducts of industries.
2. What are waterborne diseases?
Diseases that originate in water bodies or wastewater sources are called waterborne diseases.
Examples: Typhoid, Cholera, etc.
3. What are saprophytes?
The microorganisms that feed on decaying plants and animals are called saprophytes. They are responsible for recycling dead organisms.
Example: Fungi.
4. What is sludge?
The solid particles that settle down during wastewater treatment are called sludge. It is decomposed and reduced to finer particles by using saprophytic bacteria. It is often used to generate biogas.
5. What are septic tanks?
It is a water-tight container buried closer to a house where sewage is collected and decomposed naturally.