Ncert- science – class 7- Chapter 13 – Wastewater Story 1 Welcome to your Ncert- science – class 7- Chapter 13 – Wastewater Story 1 1. Which of the following is biodegradable? Orange peels Aluminium foil Plastic bottle Aluminium None 2. Bacteria that decompose organic wastes are called Lactobacillus bacteria Anaerobic bacteria Aerobic bacteria All of these None 3. An example of source reduction of waste is Backyard composting Burning Making paper aero planes Throwing things that are old None 4. The system of a network of pipes used for taking away wastewater from homes or public buildings to the treatment plant is known as sewers transport system. treatment plant. sewerage None 5. Bacteria that decompose organic wastes are called Aerobic bacteria Lactobacillus bacteria Anaerobic bacteria All of these None 6. Water polluted by various human activities causes a number of water borne diseases. Which of the following is not a water borne disease? Cholera Asthma Typhoid Dysentry None 7. Filtration plants uses _____ filters to remo paper steel sand none of these None 8. Which of the following is/are products of wastewater treatment? Sludge Biogas Both biogas and sludge Aerator None 9. Addition of harmful substance in water leads to Water pollution Algal bloom Microbial growth High oxygen demand None 10. The direct discharge of pollutants into water bodies leads to Soil pollution All of the above Water pollution Air pollution None 11. Which of the following is wastewater? Water coming out of a shower. Water trickling from a damaged tap. Water coming out of a laundry. Water flowing in a river. None 12. Which among the following are ways to conserve water? Turn off the taps while brushing teeth. Boil limited cups of water for drinking. All of the above Use less/limited water while bathing. None 13. Pick from the following one chemical used to disinfect water Silica Washing soda Coal Chlorine None 14. Open drain system is a breeding place for which of the following? Flies Organisms which cause diseases Mosquitoes All of these None 15. Which of the following is not an example of municipal solid waste? Packing materials Batteries Sewage Paper None 16. Which of the following is removed when wastewater is passed through bar screens? Pebbels Grit Sand Cans None 17. Biodegradable waste Decomposes in nature by microbes Does not decompose Enters the food chains then causes bio magnification Accumulates in environment None 18. Polythene and plastics Are non-biodegradable and very harmful Are not harmful Degrade in the environment very easily Do not generate any bad odour None 19. In a filtration plant water is filtered using layers of sand, fine gravel and medium gravel. sand and fine gravel. sand and clay. clay and fine gravel. None 20. Which of the following is a part of inorganic impurities of the sewage? Vegetable waste Pesticides Phosphates Urea None Time's up Please Share This Share this content Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Leave a Reply Cancel replyCommentEnter your name or username to commentEnter your email address to commentEnter your website URL (optional) Save my name, email, and website in this browser for the next time I comment.
