Bright Zoom Kalvi

NCERT Solutions for class 8 Science  Ch-3-Synthetic Fibers and Plastics Subjective Questions 1 Mark Question 1. Explain why some fibres are called synthetic. [NCERT] Answer: Some fibres are called synthetic because they are made by human beings. Question 2. Mark the correct answer. Rayon is different from synthetic fibres because  [NCERT] It has a silk-like appearance. It is obtained from wood pulp. Its fibres can also be woven like those of natural fibres. Answer: It is obtained from wood pulp. Question 3. Give examples which indicate that nylon fibres are very strong. Answer: Parachutes and nylon ropes are used for rock climbing. Question 4. Name the plastic whose sheets are used for packing liquids. Answer: Polythene. Question 5. Why is teflon used as tape for sealing purpose ? Answer: Becausee of its toughness, teflon is used as tape for sealing purpose. Question 6. Name the first fully synthetic fibre. Answer: Nylon. Question 7. Why nylon i...

NC ERT Solutions for class 8 Science Ch-2-Microorganisms Friend and Foe Subjective Questions 1 Mark Question 1. Name the bacteria responsible for the disease typhoid.  [MSE (Chandigarh) 2008] Answer: Salmonella typhi. Question 2. Chicken pox is caused by ………. virus.  [KVS 2008] Answer: Varicella zoster. Question 3. ………….. (disease) is caused by mycoplasma. [KVS 2008] Answer: Pleuropneumonia. Question 4. Name the toxin released by T.B. bacteria. [MSE (Chandigarh) 2007] Answer: Tuberculin toxin is released by T.B. bacteria. Question 5. Which microorganism is the cause of malaria ?  [NCT 2006] Answer: A Protozoan, Plasmodium. Question 6. Write two diseases caused by bacteria. [NCT2005] Answer: Two diseases caused by bacteria are tuberculosis and diphtheria. Question 7. Name any two items that are prepared by using yeast.  [KVS 2005] Answer: Yeast is used to prepare bread and alcohol. Question 8. Fill in the blanks :  [NCERT] Microorganis...