lecture test #3 Flashcards
(236 cards)
what are the 3 distinct internal regions of the kidney?
renal cortex, renal pelvis, and renal medulla
what is the renal cortex?
the superficial region of the kidney
what is the renal pelvis?
the region of the kidney that is continuous with the ureter. it is composed of minor calyces that collect urine from pyramidal papillae and minor calyces that collect urine from the minor calyces
what is the renal medulla?
the region of the kidney composed of medullary pyramids separated by renal columns. each pyramids and its surrounding cortical tissue is a lobe, with eight lobes in each kidney
what is the collecting duct of the nephron?
this structure is composed of simple squamous epithelium and has receptors of antidiuretic hormone (ADH). it drains the distal convoluted tubules
what is the glomerular (bowman’s) capsule of the nephron?
the site of filtrate formation. the hydrostatic pressure, also known as glomerular blood pressure, is the chief force pushing water and solutes across the filtration membrane
what is the distal convoluted tubule of the nephron?
the area of the nephron where reabsorption is hormonally regulated. this region contains microvilli, but isn’t the area of the majority of reabsorption
what is the glomerulus of the nephron?
a network of fenestrated capillaries that allow passage of some plasma elements into the glomerulus, but not large components like cells or proteins
what is the nephron loop?
the area of the nephron where its permeability determines the medullary osmotic gradient. it helps determine whether large amounts of dilute urine or small amounts of concentrated urine are formed. its thin segment aids in the passive movement of water out of the tubule. its descending limb contains fluid that becomes more concentrated as it descends and the ascending limb moves ions into interstitial space for reabsorption
what is the proximal convoluted tubule of the nephron?
the area where the majority of tubular reabsorption occurs. apical microvilli on the surface of its simple cuboidal epithelium increase surface area to increase absorption of filtrate components. these cells also have numerous mitochondria because of all the active transport occurring in region. low pressure, porous vessels reabsorb the solutes and water from this region of the nephron.
what are the major renal processes?
glomerular filtration, tubular reabsorption, and tubular secretion
what is tubular reabsorption?
reabsorption of useful substances, like water, glucose, amino acids, and electrolytes. they are transported out of the filtrate, into tubule cells and then enter capillary blood. while some of this reabsorption is passive, most of it is active. this process occurs primarily in the proximal convoluted tubule.
what is tubular secretion?
substances like hydrogen ions, potassium ions, creatinine and drugs are removed from peritubular capillary blood and secreted by tubule cells into the filtrate. this mechanism is very important for maintaining acid-base blood balance.
what is glomerular filtration?
water and solutes smaller than proteins are forced through capillary walls and the pores of the glomerular capsule into the renal tubule in a passive, non-selective process
what impact does antidiuretic hormone (ADH) have on urine or filtrate formation?
acts on the collecting duct by inserting aquaporins into the principle cells to make them more permeable to water, aiding in water reabsorption
what impact does atrial natriuretic peptide (ANP) have on urine or filtrate formation?
acts on the distal convoluted tubule and reduces blood sodium levels, therefore decreasing blood pressure
what effect does aldosterone have on urine or filtrate formation?
acts on the distal convoluted tubule and conserves sodium by aiding in sodium reabsorption. it reduces blood potassium concentration and is responsible for increasing blood pressure
what effect does parathyroid hormone (PTH) have on urine or filtrate formation?
acts on the distal convoluted tubule, where it aids in calcium reabsorption
urine is formed within the kidney. what are the structures from where urine is formed to where urine is eliminated from the body? (6 total)
- nephron
- collecting duct
- minor calyx
- major calyx
- ureter
6.urethra
what is the function of the ureters?
carries urine from the kidneys to the bladder utilizing gravity and peristalsis
what is the function of the urethra?
transports urine out of the body
what is the function of the urinary bladder?
responsible for temporary urine storage, made possible in part by the transitional epithelium its composed of
what structure receives blood that has passed through the glomerulus?
efferent arteriole
what is the structural and functional unit of the kidney?
nephron