Biology - Excretory Products and their Elimination Question with Solution | TestHub
Which is the only mode of urine formation in marine bony fishes and desert amphibians?
Options:
Answer:
Solution:
In the physiology of excretion and osmoregulation, urine formation in the kidney involves three main processes: ultrafiltration, selective reabsorption, and tubular secretion.
Tubular secretion is also referred to as augmentation, a process where metabolic wastes are actively transported from the surrounding peritubular capillaries into the lumen of the convoluted tubules.
Marine bony fishes and desert amphibians are adapted to hypertonic or highly arid environments where water conservation is critical for survival. Consequently, their kidneys are often aglomerular, meaning their nephrons lack glomeruli and Bowman capsules.
Due to the absence of a functional glomerulus, these animals cannot perform ultrafiltration or glomerular filtration. Instead, they rely entirely on the active transport of wastes directly into the renal tubules.
Therefore, tubular secretion or augmentation is the only mode of excretion in marine bony fishes and desert amphibians.
Answer: Augmentation
