Q17. What are called external parts of the body?
Q18. What is organ system?
Q19. Who tells the body parts what to do?
Q20. What are the functions of tongue?
Q21. Name the organs of the excretory system.
Or
What are the main organs of the excretory system?
Q22. What would happen if digestive system did not work properly?
Q23. Write the work performed by the brain.
Q24. Write the function of arteries.
Q25. Write the function of veins.
Q26. What is the first stage of digestion?
Or
Where does the process of digestion starts? Describe briefly.
Q27. What is the main function of lungs?
Q28. What is the function of mucus and fine hair in nostrils?
Q29. How digestion takes place in stomach?
Or
How does stomach help in the digestion of food?
Or
How is food digested in the stomach?