1. What is the main topic discussed in the section titled "The Invisible Living World: Beyond Our Naked Eye"?

2. Why might observing the hidden world of tiny living beings change the way you think about what counts as 'living'?

3. How can tiny living beings interact with each other in their environment?

4. Imagine you could see the invisible living world around you. What might you use to observe these tiny living beings?

5. What is the main function of a lens as described in the text?

6. What scientific tool helped humans see tiny living creatures that their eyes could not?

7. What are living beings, whether plants or animals, called according to the text?

8. What happens when you look at letters through a round-bottom flask filled with water?

9. Why does a flask filled with water act like a magnifying glass?

10. Why were people unable to see tiny organisms with their naked eyes for a long time?