Q1.
The young stages of frogs are called tadpoles. The tadpoles live in fresh water.
The drawings show a tadpole just before hatching and three days after hatching.
Structure X helps in the exchange of substances between the tadpole and the water.
Structure X
Tadpole just
before hatching
Tadpole three days
after hatching
(a)
Name one substance, other than food, that the tadpole needs to exchange with the
water in order to grow.