CBSE Tutorials

Month: August 2015

  • Chemistry IX | Matter-Its Nature and Behaviour | Part 1

    Matter-Its Nature and Behaviour | Part 1 INTRODUCTION Matter · Anything that occupies space , possesses mass and exert pressure is called matter. Element · An element is a substance which cannot be split up into two or more simpler substances by the any chemical and physical methods of applying heat, light or electric energy.…

  • Biology IX | Health and Diseases | Part 2

    Health and Diseases | Part 2 Disease caused by bacteria Tuberculosis (T.B.) Tuberculosis (T.B.) was first discovered by Robert Koch in 1882. It is caused by a bacterium called Mycobacterium tuberculosis. The bacterium releases a toxin called tuberculin. T.B. can affect all parts of the body. In human beings, the infection spreads by inhaling infected…