Name two non-chordate phyla, where animals are radially symmetrical.

1

(a)

Cnidaria and Echinodermata

What kind of body scales are present in bony

1

(a)

Ctenoid or cycloid scales

Name the group which lacks digestive tract.

1

(a)

Porifera

Name the cells that line the spongocoel in Sycon

1

(a)

Choanocytes (collar cells)

Give an example of animal which exhibits alternation of generation.

1

(a)

Obellia,shows alternation if asexual and sexual phases in its life cycle.

Why the heart of fishes is commonly called 'the venous heart'?

1

(a)

This is because it supplies deoxygenated blood to gills for oxygenation

Why pneumatic bones are present in birds?

1

(a)

The empty space in pneumatic bones helps in weight reduction of skeleton in birds.It is a kind of flight adaptation in birds

Write two unique features of mammals

1

(a)

Mammals are unique due to following features
(i) Presence of milk-producing mammary glands in females
(ii) Hairs present on the whole body

What is the bilateral symmetry?

1

(a)

In bilateral symmetry, the body can be divided into identical left and right halves in only one plane.

Name some diseases caused by roundworms.

1

(a)

Ascariasis caused by roundworm or Ascaris.

Difference between the complete and incomplete digestive system.

2

(a)

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

2

(a)

What is the difference between direct and indirect development?

2

(a)

Describe the type of excretory and circulatory system in Annelida.

2

(a)

Distinguish between Urochordata and Cephalochordatqa.

2

(a)

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

3

(a)

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

3

(a)

Distinguish between lizards and snakes

3

(a)

What flight adaptations are present in birds?

3

(a)

What are the modifications that are observed in birds that help them fly?

3

(a)

Describe briefly the body wall of sponges.

5

(a)

Differentiate between polyp and medusa

5

(a)

Distinguish between Chordates and Non-Chordates

5

(a)