Which of the following organisms would lose the most water by osmosis across its gills?a. marine bony fishb. sharkc. freshwater fishd. freshwater invertebrate

Complete this map, which presents the three main topics of this chapter.

Which of the following statements regarding fishes that live in fresh water is/are correct? Select True or False for each statement.T/F Water moves across the gills via osmosis until equilibrium is established, at which time the water molecules stop moving.T/F They lose water to their environment primarily through the gills. They replace this water by drinking.T/F Water enters epithelial cells in their gills via osmosis. Electrolytes leave the same cells via diffusion.T/F They have specialized epithelia that actively pump electrolytes from the environment into the blood.

Which process in the nephron is least selective?a. filtrationb. reabsorptionc. active transportd. secretion

In this schematic of urine production in a nephron, label the four processes involved and list some of the substances that are moved in each process.

Which of the following animals generally has the lowest volume of urine production?a. vampire batb. salmon in fresh waterc. marine bony fishd. freshwater flatworm

What effect does antidiuretic hormone (ADH) have on the nephron?a. It increases water permeability of the descending limb of the loop of Henle.b. It decreases water permeability of the descending limb of the loop of Henle.c. It increases water permeability of the collecting duct.d. It decreases water permeability of the collecting duct.

The high osmolarity of the renal medulla is maintained by which of the following? (A) active transport of salt from the upper region of the descending limb. (B) the loose packing of juxtamedullary nephrons. (C) diffusion of urea into the collecting duct. (D) diffusion of salt from the descending limb of the loop of Henle

The high osmolarity of the renal medulla is maintained by all of the following excepta. active transport of salt from the upper region of the ascending limb.b. the spatial arrangement of juxtamedullary nephrons.c. diffusion of urea from the collecting duct.d. diffusion of salt from the descending limb of the loop of Henle.