Name the superclass of Chordata in which lateral line sense organs are found.

How many chanbers are present in the heart of (a) Fishes (b) Frog?

Name four Chordata classes having cold blooded animals.

Identify the following fishes:

(a) Fish with 5 to 7 pairs of gills; (b) Fish with air bladder.

Give one example of (a) cartilaginous fish; (b) bony fish.