1. The reverse process of peristalsis is called

2. Where are pollen grains located in

3. which of the following is not used in human respiratory system

4. What is the name of our Galaxy

5. Blood is carried from lungs to heart by

6. The largest artery is

7. Food for algae is

8. Sound can not pass through

9. By addition of what food becomes soft and fine

10. The lightest part of atom is

11. Human heart has ...............chambers

12. Water is essential for

13. Which circuit is used in domestic wiring

14. flowers are .................part of plant

15. Bile is released by

16. In which waves particles of medium move perpendicularly

17. What is the unit of frequency

18. The rate of flow of charge is called

19. What is the mode of  transferring of heat for energy of sun reaching  us

20. There are ...............major habitats.