Question

Difficulty: MediumExcretion and Excretory Organs

Match each nitrogenous metabolic waste product or excretory pigment listed on the left with its corresponding characteristic, primary organism group, or elimination pathway on the right.

  • AmmoniaHighly toxic, water-soluble waste excreted directly into water by freshwater bony fishes
  • UreaModerately toxic waste synthesized in the liver via the ornithine cycle and excreted by mammals
  • Uric acidInsoluble, non-toxic paste excreted by birds and insects to maximize water conservation
  • Bile pigments (Bilirubin & Biliverdin)Waste products from hemoglobin breakdown produced by the liver and eliminated in feces

Answer

Ammonia matches with highly toxic, water-soluble waste excreted by freshwater bony fishes; Urea matches with moderately toxic waste synthesized in the liver and excreted by mammals; Uric acid matches with insoluble, non-toxic paste excreted by birds and insects; Bile pigments match with waste products from hemoglobin breakdown eliminated in feces.
Each excretory product corresponds directly to the organism's evolutionary adaptation for water conservation and nitrogenous toxicity management. Ammonia is excreted by aquatic fishes, urea by mammals, uric acid by birds/insects, and bile pigments by the liver via the digestive tract.

Step-by-Step Solution

1
Identify the excretory toxicity and solubility characteristics of nitrogenous wastes.
Ammonia requires large volumes of water due to high toxicity; Urea is moderately soluble and moderately toxic; Uric acid precipitates easily and requires negligible water.
Organism excretory products adapt directly to habitat water availability.
2
Map each waste product to its representative organism class and physiological process.
Aquatic teleosts excrete Ammonia; Mammals synthesize Urea in the liver; Birds/insects precipitate Uric acid; Liver excretes Bile pigments from erythrocyte breakdown.
Metabolic pathways convert nitrogenous products according to water-conservation needs.

Key Concept

Nitrogenous Waste Elimination and Liver Excretory Functions
Estimated Time:1m 30s
Rate this question