1. Where are pollen grains located in

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

3. In which waves particles of medium move perpendicularly

4. Blood is carried from lungs to heart by

5. What is the unit of frequency

6. Which circuit is used in domestic wiring

7. There are ...............major habitats.

8. flowers are .................part of plant

9. Water is essential for

10. Food for algae is

11. The reverse process of peristalsis is called

12. The largest artery is

13. The rate of flow of charge is called

14. Human heart has ...............chambers

15. What is the name of our Galaxy

16. Bile is released by

17. By addition of what food becomes soft and fine

18. The lightest part of atom is

19. Sound can not pass through

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