Points from 6th Std SSC Science book – Useful for Homibhabha Exam

Few useful points from 6th Std SSC board science textbook:

  1. Earlier, irlis or capes made of grass or sackcloth were used for protection from rain.
  2. Natural substances used to write: Tree bark, leaves, bhurjpatre, pens made from reeds, dhulpatya, stone slates, stone walls in caves, soil and colours made from plants
  3. Glass can be made from sand and calcium carbonate.
  4. Natural rubber is obtained from the gum or sap of trees. This sap is called ‘latex’.
  5. Goodyear invented vulcanization. In this process, rubber is heated with sulphur for three to four hours.
  6. The botanical name of rubber tree is ‘Hevea brasiliensis’
  7. Paper is a kind of network of cellulose fibres.
  8. From one silk cocoon, 500 metres to 1300 metres of thread can be obtained.
  9. Rayon: Cotton and wood pulp is dissolved in a chemical called sodium hydroxide. Called ‘synthetic silk’.
  10. There are altogether 22 bones in the skull, 8 in the head and 14 in the face.
  11. There are three bones in each of the ears (malleus, incus, stapes). Of these, the stapes is the smallest bone in our body. It is as small as a grain of rice and is hollow. Its shape is like that of a stirrup.
  12. Jet black hair is due to pure melanin, while brown, lighter hair is due to sulphur in the melanin and reddish hair, due to iron in the melanin.
  13. Birds like the robin and the woodcock can recognize the sound of an earthworm in the soil, and find their prey. This is because their hearing organs are very sensitive.
  14. Some species of grasshopper produce a sound by rubbing their legs together while flying in the air.