Flashcards in urinary system Deck (40)
ureters, urinary bladder, and urethra
kidneys, blood vessels
Urinary System Structures
filter waste products from the bloodstream and convert the filtrate into urine.
Regulates the volume, composition and pH of body fluids, adjusts water loss, releases of EPO and renin
Removes excess water, electrolytes and other wastes (urea, urine)
Storage of urine and excretion of urine
Regulation of erythrocyte production.
As the kidneys filter the blood, they are also indirectly measuring the oxygen level in the blood
Urinary System General Functions
depression, vessels & nerves enter/exit
under capsule, location of glomerular capsules
renal pyramids, papilla, columns
minor calyx, major calyx, renal pelvis to ureter
Renal Sinus (kidney)
Located on either side of vertebral column, left slightly superior, retroperitoneal
Reddish brown color, bean shaped with smooth surface.
Tough renal capsule (fibrous)
renal artery segmental interlobar arcuate interlobular afferent arterioles glomerulus efferent arterioles capillaries
blood supply to the kidney (Arteries)
from capillaries interlobular arcuate interlobar renal vein
blood supply to the kidney (Veins)
peritubular (cortex) or vasa recta (medulla)
blood supply to the kidney (veins)
The functional filtration unit in the kidney.
Kidneys house approx 2.5 million nephrons.
Filtration is mostly a passive process based on solute size and conc. gradients
Blood to be filtered arrives at the nephron via the glomerulus (capillary)
Types: Cortical or Juxtamedullary
Consists of the following components:
renal corpuscle (Bowman’s or glomerular capsule w/ glomerulus)
proximal convoluted tubule
distal convoluted tubule
renal tubule: PCT, loop of Henle, DCT
Actively reabsorb almost all nutrients (glucose, a.a., f.a.), electrolytes, and any plasma proteins.
Approximately 60% to 65% of the water in the tubular fluid is reabsorbed by osmosis.
The solutes and water are returned to the blood via the peritubular capillaries
Proximal Convoluted Tubule
: reabsorbs water from surrounding tissue
descending limb (nephron loop)
Na+ and Cl- are reabsorbed in the surrounding tissue
ascending limb (nephron loop)
Begins at the PCT, extends into the medulla
As solute conc. of interstitial fluid increases due to ascending limb release a conc. gradient is produced that pulls water out of the descending limb.
Thin portions of both limbs are permeable to water.
Begins at the end of the nephron loop.
Impermeable to solutes, must use active transport to pass ions (pumps regulated by aldosterone)
Reabsorption of water occurs here under the influence of two hormones:
Distal Convoluted Tubule
increase DCT absorption of Na+ and water, increase loss of K+, secreted by adrenal gland
Aldosterone (distal convoluted tubule)
reabsorption of water, increase blood volume at the kidney, secreted by post. pit
Antidiuretic hormone (ADH) (distal convoluted tub
If an individual is well hydrated, the collecting ducts simply transport the tubular fluid into the calyxes pelvis ureters
However, if an individual is dehydrated, water conservation must occur, and more-concentrated urine is produced
ADH may act on the collecting duct epithelium, making it more permeable to water from the tubular fluid.
Collecting Tubules and Collecting Ducts
Three tunics of the ureters
mucosa, muscularis, and adventitia
Long, fibromuscular tubes that conduct urine to the bladder. Each tube averages 25 cm in length and is retroperitoneal
originate at the renal pelvis and exit the hilum of the kidney
Peristaltic contractions are used to move urine to bladder.
Expandable, muscular sac, reservoir for urine. Positioned immediately superior and posterior to the pubic symphysis.
contacts the uterus posterosuperiorly and with the vagina posteroinferiorly
Females (urinary bladder)
contacts the rectum posterosuperiorly and is immediately superior to the prostate gland.
Males (urinary bladder)
: immovable portion of the urinary bladder.
Trigone (urinary blader)
mucosa, submucosa, muscularis, and adventitia
Four tunics (urinary bladder)