Topic: Food Energy and Respiration Subtopic: Introduction
How does air enter our lungs?
Answer: When we exhale, there is a pressure difference inside and outside of the lungs. To maintain that pressure air enters the lungs.
- What happens to food in stomach?
- What if cough is vigorous?
- How does blood move?
- What gas is present in cigarette?
- Why is iron important?
- Why are plant roots important?