What do you mean by true coelomates? Discuss their advantages.

 Explain the role of drag and thrust in bird flight

State whether the following statements are ‘True’ or ‘False’:
i) Bivalves have adapted for filter feeding methods.
ii) The blood of cephalopods contains haemocyanin.
iii) Cephalopods have one of the best developed nervous systems among invertebrates.
iv) Development in bivalves includes trochophore and veliger larvae. 

Which of the following is not true for animals with radial symmetry?
i) Non front and back ends
ii) Are always sessile
iii) No left or right sides
iv) Face the environment from all sides

Why do marine teleosts need to drink large amounts of seawater?

Which of the words given in the parantesis is correct?

Flame cells in platyhelmninthes are ……………….. in function. (excretory/osmoregulatory)

Choose the correct word from the alternative given:
i) Trilobites are an extinct group of primitive/advanced arthropods.
ii) Spiders, ticks, mites and scorpions are included under the class Eurypterida/Arachnida.
iii) Spinning organs or spinnerets are characterstic of Araneae/Acarina.