Water Balance 5E - Marathon Runner Biology

Vocabulary practice flashcards covering cell osmosis, renal anatomy, excretory osmoregulation, systemic water balance, aquatic osmoregulation, and hyponatremia.

Osmoregulation

The physiological process of maintaining the balance of water levels and dissolved mineral salts in the blood and bodily fluids.

Kidney

The primary organ of the excretory system that filters metabolic waste products from the blood, produces urine, and regulates water and solute balance.

Renal Artery

The blood vessel that transports unfiltered blood into the kidney.

Renal Vein

The blood vessel that carries filtered blood away from the kidney back into systemic circulation.

Ureter

The duct through which urine exits the kidney to be collected in the urinary bladder.

Antidiuretic Hormone (ADH)

A hormone secreted by the posterior pituitary gland that travels to the kidneys to stimulate water reabsorption, concentrating urine and conserving body water.

Osmoreceptors

Specialized sensory receptors that detect changes in body fluid solute concentration and blood volume to trigger thirst and hormone release.

Hyponatremia

A condition characterized by abnormally low sodium concentrations in the bloodstream, resulting from excessive water intake paired with insufficient urination.

Hypertonic Solution

An external solution with a higher solute concentration (lower water concentration) than the cytoplasm of a cell, resulting in water leaving the cell by osmosis and causing it to shrivel.

Hypotonic Solution

An external solution with a lower solute concentration (higher water concentration) than the cell interior, causing net water movement into the cell, which can lead to swelling and bursting.

Isotonic Solution

A solution that has an equal solute and water concentration to the inside of a cell, resulting in no net movement of water across the cell membrane.

Glomeruli

Capillary networks located at the start of kidney tubules where fluid and small solutes are filtered from the blood.

Chloride Secretory Cells

Specialized cells in fish gill membranes that actively transport salts across concentration gradients to maintain osmotic equilibrium in freshwater or saltwater environments.

Insensible Water Loss

Unconscious, continuous water loss from the body via evaporation through the skin and respiratory exhalation from the lungs, totaling about $0.9\,\text{L/day}$.

Metabolic Water Production

Water generated within tissues as a byproduct of cellular respiration ($\text{Glucose} + O_2 \rightarrow CO_2 + H_2O + \text{ATP}$), yielding approximately $0.3\,\text{L/day}$ ($300\,\text{mL}$).

Wet Mount

A microscope slide preparation technique in which a thin specimen slice is mounted in a drop of liquid and overlaid with a coverslip.