Biradial symmetry and lack of cnidoblasts are the characteristics of

• Starfish and sea anemone

• Ctenoplana and Beroe

• Aurelia and Paramecium

• Hydra and starfish

What are the difficulties that you would face in classification of animals, if common fundamental features are not taken into account?

If you are given a specimen, what are the steps that you would follow to classify it?

How useful is the study of the nature of body cavity and coelom in the classification of animals?

Distinguish between intracellular and extracellular digestion? 

What is the difference between direct and indirect development?

What are the peculiar features that you find in parasitic platyhelminthes?

What are the reasons that you can think of for the arthropods to constitute the largest group of the animal kingdom? 

Water vascular system is the characteristic of which group of the following: 

“All vertebrates are chordates but all chordates are not vertebrates”. Justify the statement.

How important is the presence of air bladder in Pisces?