Sections
Key Terms
Key Terms
- afferent arteriole
- arteriole that branches from the cortical radiate artery and enters the glomerulus
- ammonia
- compound made of one nitrogen atom and three hydrogen atoms
- ammonotelic
- describes an animal that excretes ammonia as the primary waste material
- angiotensin converting enzyme (ACE)
- enzyme that converts angiotensin I to angiotensin II
- angiotensin I
- product in the renin-angiotensin-aldosterone pathway
- angiotensin II
- molecule that affects different organs to increase blood pressure
- anti-diuretic hormone (ADH)
- hormone that prevents the loss of water
- antioxidant
- agent that prevents cell destruction by reactive oxygen species
- arcuate artery
- artery that branches from the interlobar artery and arches over the base of the renal pyramids
- ascending limb
- part of the loop of Henle that ascends from the renal medulla to the renal cortex
- blood urea nitrogen (BUN)
- estimate of urea in the blood and an indicator of kidney function
- Bowman's capsule
- structure that encloses the glomerulus
- calyx
- structure that connects the renal pelvis to the renal medulla
- cortex (animal)
- outer layer of an organ like the kidney or adrenal gland
- cortical nephron
- nephron that lies in the renal cortex
- cortical radiate artery
- artery that radiates from the arcuate arteries into the renal cortex
- countercurrent exchanger
- peritubular capillary network that allows exchange of solutes and water from the renal tubules
- countercurrent multiplier
- osmotic gradient in the renal medulla that is responsible for concentration of urine
- descending limb
- part of the loop of Henle that descends from the renal cortex into the renal medulla
- distal convoluted tubule (DCT)
- part of the renal tubule that is the most distant from the glomerulus
- efferent arteriole
- arteriole that exits from the glomerulus
- electrolyte
- solute that breaks down into ions when dissolved in water
- flame cell
- (also, protonephridia) excretory cell found in flatworms
- glomerular filtration
- filtration of blood in the glomerular capillary network into the glomerulus
- glomerular filtration rate (GFR)
- amount of filtrate formed by the glomerulus per minute
- glomerulus (renal)
- part of the renal corpuscle that contains the capillary network
- hilum
- region in the renal pelvis where blood vessels, nerves, and ureters bunch before entering or exiting the kidney
- inferior vena cava
- one of the main veins in the human body
- interlobar artery
- artery that branches from the segmental artery and travels in between the renal lobes
- juxtaglomerular cell
- cell in the afferent and efferent arterioles that responds to stimuli from the macula densa
- juxtamedullary nephron
- nephron that lies in the cortex but close to the renal medulla
- kidney
- organ that performs excretory and osmoregulatory functions
- lobes of the kidney
- renal pyramid along with the adjoining cortical region
- loop of Henle
- part of the renal tubule that loops into the renal medulla
- macula densa
- group of cells that senses changes in sodium ion concentration; present in parts of the renal tubule and collecting ducts
- Malpighian tubule
- excretory tubules found in arthropods
- medulla
- middle layer of an organ like the kidney or adrenal gland
- microvilli
- cellular processes that increase the surface area of cells
- molality
- number of moles of solute per kilogram of solvent
- molarity
- number of moles of solute per liter of solution
- mole
- gram equivalent of the molecular weight of a substance
- nephridia
- excretory structures found in annelids
- nephridiopore
- pore found at the end of nephridia
- nephron
- functional unit of the kidney
- non-electrolyte
- solute that does not break down into ions when dissolved in water
- osmoconformer
- organism that changes its tonicity based on its environment
- osmoregulation
- mechanism by which water and solute concentrations are maintained at desired levels
- osmoregulator
- organism that maintains its tonicity irrespective of its environment
- osmotic balance
- balance of the amount of water and salt input and output to and from a biological system without disturbing the desired osmotic pressure and solute concentration in every compartment
- osmotic pressure
- pressure exerted on a membrane to equalize solute concentration on either side
- perirenal fat capsule
- fat layer that suspends the kidneys
- peritubular capillary network
- capillary network that surrounds the renal tubule after the efferent artery exits the glomerulus
- proximal convoluted tubule (PCT)
- part of the renal tubule that lies close to the glomerulus
- renal artery
- branch of the artery that enters the kidney
- renal capsule
- layer that encapsulates the kidneys
- renal column
- area of the kidney through which the interlobar arteries travel in the process of supplying blood to the renal lobes
- renal corpuscle
- glomerulus and the Bowman's capsule together
- renal fascia
- connective tissue that supports the kidneys
- renal pelvis
- region in the kidney where the calyces join the ureters
- renal pyramid
- conical structure in the renal medulla
- renal tubule
- tubule of the nephron that arises from the glomerulus
- renal vein
- branch of a vein that exits the kidney and joins the inferior vena cava
- renin-angiotensin-aldosterone
- biochemical pathway that activates angiotensin II, which increases blood pressure
- segmental artery
- artery that branches from the renal artery
- semi-permeable membrane
- membrane that allows only certain solutes to pass through
- transport maximum
- maximum amount of solute that can be transported out of the renal tubules during reabsorption
- tubular reabsorption
- reclamation of water and solutes that got filtered out in the glomerulus
- tubular secretion
- process of secretion of wastes that do not get reabsorbed
- urea cycle
- pathway by which ammonia is converted to urea
- ureotelic
- describes animals that secrete urea as the primary nitrogenous waste material
- ureter
- urine-bearing tube coming out of the kidney; carries urine to the bladder
- uric acid
- byproduct of ammonia metabolism in birds, insects, and reptiles
- urinary bladder
- structure that the ureters empty the urine into; stores urine
- urine
- filtrate produced by kidneys that gets excreted out of the body
- vasa recta
- peritubular network that surrounds the loop of Henle of the juxtamedullary nephrons
- vasodilator
- compound that increases the diameter of blood vessels
- vasopressin
- another name for anti-diuretic hormone