Asked in ETEA MDCAT 2011 2011Moderate

Malphigian tubules convert nitrogenous waste into:

Correct answer: C. uric acid

  • A. urine
  • B. ammonia
  • C. uric acid
  • D. urea

Explanation

Malphigian tubules are specialized excretory organs found in insects like cockroaches. They convert nitrogenous waste into uric acid, a compound that can be excreted with minimal water loss. This is particularly advantageous for water conservation in terrestrial environments. Option C is correct because uric acid is the end product of nitrogenous waste processing in these tubules. Option A (urine) and Option D (urea) involve more water for excretion, which is not as efficient in conserving water. Option B (ammonia) is highly toxic and requires a lot of water to be excreted safely, making it unsuitable for organisms relying on Malphigian tubules.

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