The nurse is providing care for a client with a fluid imbalance. The nurse explains that in the body, areas with high concentration of solutes naturally and passively shift to areas of lower concentration. The nurse is describing which process?

Choice A reason: Pale yellow is the normal color of urine, indicating adequate hydration and no bilirubin in the urine. Bilirubin is a pigment that is produced when red blood cells are broken down. It is normally excreted in the bile, but if the bile duct is obstructed, it can accumulate in the blood and urine, causing jaundice and dark urine.

Choice B reason: Red urine can indicate blood in the urine, which can be caused by various conditions such as urinary tract infection, kidney stones, trauma, or cancer. It is not related to bile duct obstruction or cholecystitis.

Choice C reason: Greenish-brown urine can indicate bilirubin in the urine, which can be caused by bile duct obstruction or liver disease. It is a sign of cholestasis, which is a reduced or stopped flow of bile. The nurse should monitor the client for other signs of cholestasis such as jaundice, clay-colored stools, pruritus, and abdominal pain.

Choice D reason: Dark and concentrated urine can indicate dehydration, which can be caused by various factors such as fluid loss, fever, vomiting, or diarrhea. It is not related to bile duct obstruction or cholecystitis.

Choice A reason: Active transport is not the process that allows fluid to pass through a membrane from a dilute to a more concentrated area. Active transport is the process that moves solutes across a membrane against their concentration gradient, using energy from ATP. Active transport can create or maintain a concentration difference between two sides of a membrane.

Choice B reason: Osmosis is the process that allows fluid to pass through a membrane from a dilute to a more concentrated area. Osmosis is the movement of water across a selectively permeable membrane from an area of low solute concentration to an area of high solute concentration. Osmosis can equalize the concentration of solutes on both sides of a membrane.

Choice C reason: Filtration is not the process that allows fluid to pass through a membrane from a dilute to a more concentrated area. Filtration is the movement of fluid and solutes across a membrane due to a pressure difference between two sides of a membrane. Filtration can separate solutes from fluid based on their size and charge.

Choice D reason: Diffusion is not the process that allows fluid to pass through a membrane from a dilute to a more concentrated area. Diffusion is the movement of solutes across a membrane from an area of high solute concentration to an area of low solute concentration. Diffusion can also equalize the concentration of solutes on both sides of a membrane.