1) What can be observed after five days?
....The tadpoles(蝌蚪) in beaker S died. The tadpoles in beaker T are still alive.
2) Write one reason to explain your answer in (1)
.....The oil layer in beaker S prevents(防止) the air from dissolving(溶化) in the water, the tadpoles do not have oxygen supply(供应).
.....The oil layer in beaker S prevents(防止) the air from dissolving(溶化) in the water, the tadpoles do not have oxygen supply(供应).
3) What can be concluded in this experiment?
....Tadpoles need air to stay alive.
....Tadpoles need air to stay alive.
4) Name two other basic needs of the tadpole.
.....water and food
.....water and food
