Question

The body cells in cockroach discharge their nitrogenous waste in the haemolymph mainly in the form of

• A. Ammonia
• B. Potassium urate
• C. Urea
• D. Calcium carbonate

Answer 1

Answer: (B)

• Cockroach excretes nitrogenous waste in the form of soluble potassium urate which is liberated into the haemolymph and taken up by the cells lining the Malpighian tubules.

• The tubules facilitate the absorption of urate by stirring up the blood.
• In the cells of the tubule the potassium urate reacts with water and carbon dioxide to form potassium hydrogen carbonate and uric acid. The former is absorbed back into the blood, while the later is excreted.

So, the correct option is 'Pottasium urate'.