Hard calcium carbonate structures are used as a skeleton by

State reasons for the following:
$(i)$ Tapeworms do not have a digestive tract.
$(ii)$ Frogs have both skin and lungs for breathing.
$(iii)$ $A$ whale is a mammal,not a fish.

Which of the following is not an aquatic animal?

Identify and write the names of the parts labeled as $A, B, C$ and $D$ in the given figure of a seahorse in your answer book.

Name two egg-laying mammals.

Amphibians do not have which of the following?