Osmoregulation and Excretion exam Flashcards

The homeostatic mechanism that allows organisms to balance their solute concentration and deal with water loss.

To filter blood plasma and form urine, playing a crucial role in osmoregulation and elimination of nitrogenous waste.

The structure in the nephron where filtration occurs, consisting of the glomerulus and Bowman's capsule.

To establish osmotic gradients essential for water and salt reabsorption.

A hormone secreted by the pituitary gland that increases water reabsorption in the kidneys by adding aquaporins to the apical membrane.

To regulate blood pressure and volume by increasing salt and water reabsorption in the kidneys.

Waste products like ammonia, urea, and uric acid that result from the breakdown of proteins and nucleic acids.

Many marine organisms are osmoconformers, meaning they are isoosmotic with their environment and do not actively regulate their internal osmolarity.

The part of the nephron where selective reabsorption of water, ions, and nutrients occurs.

Cortical nephrons have tubules that extend only a little into the medulla, while juxtamedullary nephrons extend deeply into the medulla and help maintain osmotic gradients.

A measure of solute concentration, defined as moles of dissolved solute per liter of solution.

Aldosterone stimulates the distal tubules and collecting duct to reabsorb more salt, which leads to increased water reabsorption and higher blood volume.

The process in the renal corpuscle where water and small solutes cross the epithelial membrane to form filtrate.

Specific wastes and solutes are actively added back into the filtrate from the blood to help maintain osmotic balance and remove toxins.

Organisms that are isoosmotic with their environment and do not actively regulate their internal osmolarity.

Aquaporins are water channels that facilitate the rapid transport of water across cell membranes.

An adaptation that allows organisms to survive extreme desiccation by essentially drying out and still remaining viable.

The vasa recta surrounds the loop of Henle and helps maintain the osmotic gradient necessary for water and salt reabsorption.

A system in the loop of Henle that expends energy to create a strong concentration gradient for efficient water and salt reabsorption.

The juxtaglomerular cells in the kidneys release renin in response to low blood pressure or blood volume.

A type of passive transport where molecules move across the membrane using protein channels or carrier proteins.

To actively reabsorb solutes and water, connecting the loop of Henle to the collecting duct.

Transport that directly hydrolyzes ATP to power protein pumps, such as the sodium-potassium pump.

To reabsorb water and urea, and to be the final site of urine concentration before excretion.

A solution with a higher osmolarity compared to another solution, causing water to leave cells.

ADH decreases blood osmolarity by increasing water reabsorption in the kidneys.

A less toxic nitrogenous waste product formed by combining ammonia and CO2, excreted with minimal water loss.

Angiotensin II raises blood pressure by vasoconstriction and stimulates the release of aldosterone and ADH.

The ability of a membrane to allow some substances to pass through while blocking others, often due to the presence or absence of transport proteins.