BIOL 1202 Chapter : Bio 11 26
Document Summary
An aquatic animal uses gills to take up salts. 44. 2 an animal"s nitrogenous wastes reflect its phylogeny and habitat. Diffuses across the body surface or at gills. Ammonia converted to urea in the liver, concentrated in the kidneys. Secreted as a paste with minimum water loss. Keep high concentrations of urea in their bodies. Diverse excretory systems are variations on a tubular theme. Most excretory systems produce urine by refining a filtrate derived from bodily fluids. Filtration: pressure filtering of body fluids, producing the filtrate. Secretion: the addition of toxins and other solutes from body fluids to the filtrate. System of tubules that run through the body. At the ends there are bulbs with a tuft of cilia that helps pump out the excess water to the environment. Each segment of the worm has a series of tubes that filters fluids. The kidneys are the primary site of water balance and salt regulation.
