Q17 of 63 Page 195

Enumerate the characteristic of a class that contains organisms with two types of symmetry in their life cycle.

Two types of symmetry, i.e. bilateral and radial both is found in phylum Ctenophora. The characters are:

1. Incomplete gut, only mouth present.


2. No organ for excretion, respiration or circulation.


3. Diploblastic.


4. Biradially symmetrical


5. Eight rows of ciliated comb-like structures.


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Anukool’s father works for an international bank and has been transferred to Paris. He stayed in a rented house there. People in his office have come from different countries and speak various language viz. Dutch, French, Urdu, and English. Due to different mother tongues, he is finding it difficult to communicate with others and hence, could not work efficiently.

One day, he told his communication problem to his son. Anukool discussed his father’s problem with his teacher and then called him up next day to give his advice.


(i) What advice did Anukool give to his father?


(ii) List two advantages of speaking the same language all over the world.


(iii) What value shown by Anukool by his action?