Rivers of life

1.       What are the basic materials that are needed by all living beings to survive?

- Food, water and air.

2.       What happens to the food we eat?

-it gets digested into simple absorbable substances called as nutrients in the digestive system to               give us energy and the waste is expelled out.

3.       What happen to the air we breathe?

-Our lungs absorbs oxygen and give out carbon dioxide.

4.        Name the only vein which carries oxygen- rich blood?

 (pulmonary vein)

5.       What is the structure of heart?

-  It is hollow, muscular bag like organ, made up of powerful muscles and shape like upside down pear.              

6.       What is septum? (

-The heart is divided into left and right parts by a thick vertical muscular wall called septum.

   -   7.Which organ system in human beings is responsible for removal of majority of urea and uric               acid /  waste materials from the human body?

           -Human urinary system

      8. Why is the process of sweating important for us?

          -  It helps in maintaining body temperature.