These calluses are mosquito larvae. They live in water. Some students asked, "Do calluses living in water need air?" Please design an experiment to help him explore this problem.

The experimental materials provided are: water, beaker and fine copper wire mesh.

1, explore, your hypothesis is:

2. How to design a controlled experiment?

3. Your expected experimental results are:

4. You analyzed the reasons for this result:

5, you come to the conclusion that:

1, assuming that living in water requires air.

2. Experiment: Take out two beakers with the same model, respectively labeled as A and B, and inject equal amount of water into the beakers. Each beaker is filled with 10 sponge, and a thin copper wire is placed at12 of the water level of Beaker B (to prevent the sponge from touching the water surface). Beaker A is not used.

3. Results: The swallow in beaker A survived normally after a period of time, while the swallow in beaker B weakened or died.

4. Reason: Because the surface layer is rich in dissolved oxygen, the calluses in B are blocked by fine copper wire mesh and cannot reach the surface layer, and the calluses are weak or die due to lack of oxygen.

5. Conclusion: Eighty-year-old people living in water need air.