Osmoregulation and Excretion Flashcards

Vocabulary flashcards covering key terms and concepts from the Osmoregulation and Excretion lecture.

Osmoregulation

Regulates solute concentrations and balances the gain and loss of water.

Osmolarity

The solute concentration of a solution, determining the movement of water across a selectively permeable membrane.

Isoosmotic

Having the same osmolarity, resulting in no net movement of water.

Hypoosmotic

Having a lower solute concentration, leading to water movement towards a hyperosmotic solution.

Hyperosmotic

Having a higher solute concentration, drawing water from a hypoosmotic solution.

Excretion

The process of removing nitrogenous metabolites and other waste products from the body.

Ammonia

Nitrogenous breakdown product of proteins and nucleic acids; very toxic and requires lots of water for excretion.

Urea

Less toxic nitrogenous waste produced in the liver of mammals and most adult amphibians; requires less water for excretion than ammonia.

Uric Acid

Relatively nontoxic nitrogenous waste excreted by insects, land snails, and many reptiles (including birds); secreted as a paste with little water loss.

Excretory Systems

Excretory systems regulate solute movement between internal fluids and the external environment.

Filtration

Filtering of body fluids.

Reabsorption

Reclaiming valuable solutes.

Secretion

Adding nonessential solutes and wastes from the body fluids to the filtrate.

Excretion

Processed filtrate containing nitrogenous wastes, released from the body.

Protonephridia

A network of dead-end tubules connected to external openings that excrete a dilute fluid and function in osmoregulation.

Metanephridia

Consist of tubules that collect coelomic fluid and produce dilute urine for excretion.

Malpighian Tubules

Remove nitrogenous wastes from hemolymph and function in osmoregulation in insects and other terrestrial arthropods.

Kidneys

Excretory organs of vertebrates that function in both excretion and osmoregulation.

Nephron

The functional unit of the kidney responsible for filtering blood and producing urine.

Antidiuretic Hormone (ADH)

A hormone that makes the collecting duct epithelium more permeable to water, helping to conserve water.

Renin-Angiotensin-Aldosterone System (RAAS)

Part of a complex feedback circuit that functions in homeostasis; increases blood volume and pressure.