Multiple choice The excreta of lizards and birds contains a white component which is chemically ______. Urea Uric acid Creatinine Precipitated calcium Reveal answer Fill a bubble to check yourself B Correct answer Explanation Birds and lizards are uricotelic, meaning they excrete nitrogenous waste primarily in the form of uric acid. This is a water-conserving adaptation, as uric acid is relatively insoluble and excreted as a white paste.