NCERT 6th Class (CBSE) Science: Garbage In, Garbage Out

Question: Why should we be careful in using plastic bags to store cooked food items?

Answer:

1.  Sometimes the plastic bags may not be suitable for keeping eatables.Consuming food packed in such plastic bags could be harmful to our health.
2.  Many a time shopkeepers use plastic bags that have been used earlier for other purpose.
3.  Sometimes bags collected by rag pickers are also used after washing them. Use of such recycled plastic bags to keep food items could be harmful for our health. So, shopkeepers can be stressed upon the use of plastic bags approved by the authorities.

Question: List the steps for preparing vermicompost.

Answer:

1. Dig a pit about 30 cm deep or select a wooden box.
2. Spread a net or chicken mesh at the bottom .of pit or box. You can also spread 1 to 2 cm thick layer of sand.
3. Spread some vegetable wastes including peels of fruits over the sand layer. You can use green leaves, husk or pieces of newspaper, dried stalks of plants and dried animal dung.
4. Sprinkle some water to make the layer wet. Do not
   (a)Use excess of water
   (b)Press layer of leaves or waste so that it has sufficient air and moisture,
5. Now, buy some redworms and put them in the pit.
6. Cover them loosely with a gummy bag or an old sheet of cloth or a layer of grass.
7. Red worms need food. So you can provide them as food—vegetable and fruit peels, coffee and tea remains and weeds from the field or garden. Bury this food about 2-3 cm inside the pit.
8. Do not put salt, pickles, oil, vinegar, meat and milk preparations. This may cause growth of disease-causing organisms. Red worms do not survive in very hot or very cold surroundings.
9. After 3-4 weeks, put some waste food in one comer of the pit. Most of the worms will shift towards newly added food.
10. Remove the compost from the vacated part and dry it in the sun for a few hours. The vermicompost becomes ready for use.

Question: Observe the bins and waste material heaps and suggest what materials can be used for preparing handicrafts materials.

Answer: The following handicraft items can be prepared from the waste materials usually seen in bins and waste storage.

1. Designs and sceneries on cardboard, pencil scrab can be used.
2. We can prepare basket, toys, flower vase, etc.
3. Egg trays can be prepared by papier-mache prepared from waste paper decorated with the help of different colours and can be used.
4. Empty earthen cup (kullarh) can be used as Janjhi by making small hole in it and putting a burnt candle. Light comes out in different designs.
5. Flower vase can be prepared with the help of ice-cream sticks.
6. Different types of toys are prepared with the help of plastic cup, spoon, plate, forks.
7. Models of historical monuments can be designed with the help of empty injection bottles and amputes.

You can prepare other objects with the help of your friends, brothers, sisters, relatives, parents and teachers.