Lect. 19 - Urinary system Flashcards
name the 4 structures of the urinary systm
kidneys
ureters
urinary bladder
urethra
name 2 retroperitoneal organs
kidneys and pancreas
t/f R kidney is higher than left
false, it is lower
kidney is found btw ___ and ___ vertebrae
T12 and L3
fissure through which the ureter, renal artery and vein, lymphatic vessels and nerves enter and/or leave the kidney
renal hilus
3 layers covering the kidney
- renal capsule (deep)
- adipose capsule (intermediate)
- renal fascia (superficial)
which layer of kidney forms a barrier against trauma and help maintain the shape of the kidney?
renal capsule
which layer is a mass of fatty tissue surrounding the renal capsule, protecting against trauma and helps hold the kidneys in place within the abdominal cavity&
adipose capsule
which layer anchors the kidney to surrounding structures and is deep peritoneum (on anterior surface)?
renal fascia
what is nephroptosis
floating kidney
= inferior displacement of the kidney due to a deficient adipose capsule or renal fascia
on which population does a floating kidney occur more often
very thin people
what is the consequence of nephroptosis in serious cases
the ureter may kink and block the flow of urine
what is the renal cortex
superficial, extends from the renal capsule to the base of the pyramids and spaces between the pyramids
what is the space between the pyramids
renal columns
all of the pyramids together make up the ___ ____
renal medulla
how do we name the apex of the renal pyramids, pointing towards the center of the kidney
renal papilla
what is comprised in one renal lobe (3)
1 renal pyramid, its overlying renal cortex and a little bit of renal columns on each sides
functional portion of the kidney
parenchyma
parenchyma contains about 1 million microscopic structures called ___
nephrons
urine formed by the nephrons drains into large ___ ___
papillary ducts
papillary ducts drain into ___ ____ which in turn drain into ___ ___
minor calyces, major calyces
one minor calyces receives urine from ___ ___ and delivers it to a ____ ___
renal papilla, major calyces
urine then drains from the major calyces into the ___ ___ and then through the ___ into the urinary bladder
renal pelvis, ureter
expanded area of the renal hilus
contains the calyces, part of the renal pelvis, renal blood vessels and nerves
renal sinus
3 general functions of the kidney
- regulation of blood volume and composition
- regulation of blood pressure
- contribution to metabolism
role of regulation of blood volume and composition of the kidneys (3)
removes wastes
formation of urine
help control blood pH by excreting excess H+
role of regulation of blood pressure of the kidneys (1)
secretion of the enzyme RENIN
role of RENIN
activates the renin-angiotensin pathway which results in an increase in blood pressure
role of contribution to metabolism of the kidneys (3)
synthesis of new glucose molecules during periods of fasting or starvation
secretion of erythropoietin (RBC)
participate in synthesis of vitamin D
kidneys receive __ to ___% of the cardiac output
20-25%
within each kidney, the renal artery divides into ___ aa. which branch into ___ aa.
segmental aa (lobar), interlobar aa.
at the base of the pyramids, the interlobar aa. arch between the medulla and the cortex and form the ____ aa.
arcuate aa.
arcuate arteries then branch into ___ aa. which then branch off into afferent arterioles (entering the glomerulus)
interlobular aa.
each nephron receives one ___ arteriole which divides to form a glomerulus (small tangled capillary network), and then capillaries reunite to form an ___ arteriole
afferent, efferent
t/f Vasodilation and vasoconstriction of afferent / efferent can produce large changes in the renal blood flow and vascular resistance affecting the entire systemic circulation
true
efferent arteriole divide to form a network of capillaries called ___ capillaries
peritubular
blood leaves the kidney through the __ ___
renal vein
extend from some efferent arterioles and supply the tubular portions of the nephrons in the renal medulla
vasa recta
nerve supply of the kidney
originate from the celiac ganglia
pass through the renal plexus
functional unit of the kidney
nephron
t/f we produce new nephron as we grow up
false, # remains constant after birth
3 basic functions of the nephron
- filter blood (glomerular filtration)
- return useful substances to the blood (tubular reabsorption)
- remove substances that are not needed by the body (tubular secretion)
nephron as 2 parts
renal corpuscle
renal tubule
renal corpuscle function
plasma filtration
renal tubule function
passage of filtered fluid
renal corpuscle has 2 components
glomerulus
glomerular (Bowman’s) capsule
renal tubule has 3 sections
proximal convoluted tubule
loop of henle
distal convoluted tubule
renal corpuscle and both convoluted tubules lie in the ___ ___ while loop of henle lies within the ____
renal cortex, medulla
several distal convoluted tubules empty into a single ___ ___
collecting duct
collecting ducts converge to form ___ ___, which drain into the minor and the major calyces
papillary ducts
glomerular capsule consists of 2 layers
visceral and parietal layers
the visceral layer of the glomerular capsule consists of epithelial cells called ____
podocytes
the ___ layer of the glomerular capsule forms the outer wall of the capsule
parietal
80-85% of nephrons are ___ nephrons
cortical
what is a cortical nephrons in simple terms
when the renal corpuscles lie in the superior portion of the cortex, with a short loop of henle
15-20% of nephrons are ___ nephrons
juxtamedullary
what is a juxtamedullary nephrons in simple terms
renal corpuscles lie deep in the cortex, close to the medulla, with long loops of henle
in each nephron, the last part of the ascending limb of loop of henle comes in contact with the afferent arteriole serving the renal corpuscle. tubules cells in that area are known as ___ ___
macula densa
both the macula densa and the juxtaglomerular cells (on the wall - smooth muscle fibers) make up the ___ ____
juxtaglomerular apparatus
2 types of cells are present in the distal convoluted tubule and in the collecting ducts
- principle cells
2. intercalated cells
cells that are receptors for both ADH (anti-diuretic hormone) and aldosterone (sodium and water reabsorption, potassium secretion)
principle cells
cells that play a key role in the homeostasis of blood pH
intercalated cells
renal tubules drain into __ ___ that in turn drain into large papillary ducts
collecting ducts
glomerular filtration - fluid entering the capsular space
glomerular filtrate
t/f more than 99% of the glomerular filtrate returns to the bloodstream via tubular reabsorption
true
endothelial cells from the glomerular capillaries and podocytes form a leaky barrier called the __ __
filtration membrane
glomerular filtration - filtered substances pass through 3 barriers
- glomerular epithelial cells
- basal lamina
- a filtration slit formed by a podocyte
glomerular filtration - which barrier allows all solute in the blood plasma to exit the capillary but prevent filtration of blood cells and platelets
glomerular epithelial cells
glomerular filtration - which barrier prevents filtration of large plasma proteins
basal lamina
glomerular filtration - which barrier allows the passage of water, glucose, vitamins, amino-acids, very small plasma proteins, ammonia, urea and ions
a filtration slit formed by a podocyte
glomerular filtration - contractile cells that help regulate glomerular filtration
mesangial cells
tubular reabsorption mainly occurs where
at the proximal convoluted tubule
what is the role of diuretics
slow down renal reabsorption of water and in turn cause diuresis
what is diuresis
increases urination rate
2 major outcomes of tubular secretion
H+ secretion helps control blood pH
secretion of other substances help eliminate them from the body
