Urine Concentration and Dilution

Vocabulary flashcards related to urine concentration, dilution, and associated terms and processes.

Urea handling

The process by which the nephron manages and processes urea during urine formation.

Corticopapillary osmotic gradient

The osmotic gradient created in the kidney that aids in water reabsorption, influenced by urea recycling.

ADH action in the nephron

Antidiuretic Hormone (ADH) promotes water reabsorption, increases permeability of the collecting ducts, and regulates osmotic balance.

Hyperosmotic urine

Urine that has a higher osmolarity than blood plasma, often produced in dehydration.

Hypo-osmotic urine

Urine that has a lower osmolarity than blood plasma, often produced in overhydration.

Urine characteristics

Includes factors such as color, clarity, odor, pH, specific gravity, and composition.

Specific gravity of urine

A measure of the concentration of solutes in the urine, used to assess renal function.

Polyuria

Excessive production of urine.

Oliguria

Abnormally low urine output.

Anuria

Absence of urine production.

Dysuria

Painful or difficult urination.

Stranguria

A slow and painful urination.

Urea handling

The process by which the nephron manages and processes urea during urine formation.

Corticopapillary osmotic gradient

The osmotic gradient created in the kidney that aids in water reabsorption, influenced by urea recycling.

ADH action in the nephron

Antidiuretic Hormone (ADH) promotes water reabsorption, increases permeability of the collecting ducts, and regulates osmotic balance.

Hyperosmotic urine

Urine that has a higher osmolarity than blood plasma, often produced in dehydration.

Hypo-osmotic urine

Urine that has a lower osmolarity than blood plasma, often produced in overhydration.

Urine characteristics

Includes factors such as color, clarity, odor, pH, specific gravity, and composition.

Specific gravity of urine

A measure of the concentration of solutes in the urine, used to assess renal function.

Polyuria

Excessive production of urine.

Oliguria

Abnormally low urine output.

Anuria

Absence of urine production.

Dysuria

Painful or difficult urination.

Stranguria

A slow and painful urination.

Glomerular Filtration Rate (GFR)

A measure of how much blood the glomeruli filter per minute, indicating overall kidney function.

Micturition

The process of urination or voiding urine from the bladder.

Urea recycling

The process where urea reabsorbed from the collecting ducts into the medulla contributes to the corticopapillary osmotic gradient.

Loop of Henle

A U-shaped tubule in the nephron primarily responsible for establishing the osmotic gradient in the renal medulla through countercurrent multiplication.

Collecting Ducts

The final tubes in the kidney that collect urine from nephrons, where final adjustments to water and electrolyte balance occur under hormonal control.

Renal Corpuscle

The initial blood-filtering component of the nephron, consisting of the glomerulus and Bowman's capsule.

Proximal Convoluted Tubule (PCT)

The segment of the nephron responsible for the reabsorption of the majority of filtered substances, including water, ions, and nutrients.

Distal Convoluted Tubule (DCT)

The segment of the nephron where fine-tuning of ion and water reabsorption occurs under hormonal control, particularly for sodium, potassium, and calcium.

Juxtaglomerular Apparatus (JGA)

A specialized structure formed by the distal convoluted tubule and the afferent arteriole, crucial for regulating blood pressure and glomerular filtration rate.

Renal Threshold

The plasma concentration of a substance at which it begins to appear in the urine because the transporters for that substance in the renal tubules become saturated.

Aldosterone

A steroid hormone produced by the adrenal cortex that regulates sodium and potassium balance, primarily by increasing sodium reabsorption and potassium secretion in the collecting ducts and DCT.

Renin-Angiotensin-Aldosterone System (RAAS)

A hormonal system that regulates blood pressure and fluid balance by affecting sodium and water reabsorption and systemic vasoconstriction.

Vasa Recta

Capillary networks that surround the Loop of Henle in the renal medulla, maintaining the corticopapillary osmotic gradient by preventing washout of solutes.