A&PII Lab 14: The Urinary System Flashcards
Excretion
process of the kidneys removing metabolic wastes, toxins, excess ions, and water that leave the body as urine, while returning needed substances back to the blood
Renal hilus
concave side of the kidney facing medially
Renal fascia
strands of dense irregular connective tissue; attach the kidney to the posterior abdominal wall
Renal capsule
thin shell that forms the outer layer of the kidney
Adipose capsule
between the renal capsule and renal fascia is this cushion of fat that helps protect the kidney from injury
Renal cortex
outermost region of the kidney; appears slightly granular
Renal medulla
deep to the renal cortex, this layer of the kidney appears striated due to the presence of tubules and ducts extending through
Renal pyramids
the renal medulla includes numerous of these prism-like structures
Renal columns
between the renal pyramids are granular areas similar in appearance to the renal cortex
Renal papilla
apex of the renal pyramids; points to the innermost region of the kidney
Renal pelvis
innermost region of the kidney
Nephrons
urine is formed from processes occurring within these structures located within the cortex and renal medulla; functional subunits of the kidneys
Minor calyces
the renal pelvis includes these cup-like extensions that collect urine from the renal papilla
Major calyx
several minor calcyes connect to this larger structure
Ureters
tubes connecting the kidneys with the urinary bladder
Renal sinus
fat-filled depression surrounding the renal pelvis at the renal hilus
Renal artery
within each kidney, this artery divides to form 2+ segmental arteries
Segmental arteries
arteries that divide to form lobar arteries
Lobar arteries
arteries extending between renal pyramids
Arcuate arteries
at the base of each pyramid, the interlobars branch to form these arteries that extend along the base
Interlobar arteries
the arcuates give off numerous interlobular arteries, which extend through the renal cortex
Afferent arteriole
small artery extending to each nephron to supply the glomerulus
Glomerulus
ball of capillaries supplied by an afferent arteriole extending to each nephron
Efferent arterioles
the path by which blood exits the glomerulus; carry blood to a 2nd capillary network of the nephron (peritubular capillaries)
Peritubular capillaries
2nd capillary network of the nephron
Vasa recta
blood supply of the kidney; a series of straight capillaries in the medulla
Ureters
2 narrow tubes that channel urine from the kidneys to the urinary bladder
Urinary bladder
hollow sac located at the base of the abdominopelvic cavity that collects urine and stores it temporarily
Rugae
when the bladder is empty, the mucous membrane contains these folds, which flatten when the bladder fills with urine to increase its capacity
Detrusor muscle
muscularis which contracts to expel urine from the bladder
Ureteral openings
2 posterior openings of the bladder
Internal urethral orifice
single anterior opening of the bladder
Trigone
triangle formed by the 3 openings of the bladder
Urethra
tubular organ that carries urine from the bladder to the exterior during voiding
Micturition
urination/voiding
External urethral orifice
opening of the bladder to the exterior
Internal urethral sphincter
layer of circular smooth muscle near the internal urethral orifice
External urethral sphincter
embedded within the urogenital diaphragm is this layer of skeletal muscle; voluntary muscle that permits urine to flow through the external urethral orifice
Prostatic urethra
most proximal segment of the male urethra, extending from the internal urethral orifice through the soft prostate gland
Membranous urethra
middle segment of the male urethra, which passes through the urogenital diaphragm
Spongy (penile) urethra
distal segment of the male urethra; passes through the penis and terminates at the external urethral orifice
Renal corpuscle
1 of 2 nephron parts; filters blood as the 1st step in urine formation
Renal tubule
1 of 2 nephron parts; where the filtrate is modified by the reabsorption of water and sodium and the secretion of excess ions
Glomerulus
capillary network within a nephron
Glomerular (Bowman’s) capsule
glomerulus is enclosed within this cup-shaped structure
Capsular space
interior of the glomerular capsule
Proximal convoluted tubule
1st segment of the renal tubule; begins from its union with the renal corpuscle; primary site for reabsorption, in which water and solutes pass from the filtrate to the interstitial fluid and onward into nearby capillaries
Descending limb of the loop of Henle
as the renal tubule descends into the renal medulla, it forms this; here, about 15% of the water in the filtrate is reabsorbed
Ascending limb of the loop of Henle
ascending component of the renal tubule; permeable to sodium and chloride but impermeable to water; where reabsorption of solutes occur
Distal convoluted tubule
within the renal cortex, the tubule makes several twists to form this tubule; reabsorbs a small amount of water and solutes; secretion is the primary function (excess ions are transported from the blood and interstitial fluid into the renal tubule)
Collecting duct
distal convoluted tubules from several nephrons drain into this, which descends through a renal pyramid; cells forming these include receptors for ADH, which increases reabsorption of water to produce a more solute-concentrated urine
Peritubular capillaries
low-pressure vessels branching from the efferent arteriole, which are adjacent to the renal tubules primarily in the renal cortex
Vasa recta
capillaries that parallel the loops of Henle in the medulla
Juxtaglomerular apparatus
region of cells in the nephron that participates in blood pressure regulation
Visceral layer
inner layer of the glomerular capsule wall adjacent to the glomerulus
Parietal layer
outer layer of the glomerular capsule
Podocytes
foot-like processes that wrap around the walls of the glomerulus to form part of the filtration membrane
