EX3 Histology - Urinary System Flashcards
What are the components of the urinary system
paired kidneys
paired ureters
urinary bladder
urethra
What are the seven main functions of the urinary system
regulation of blood ion composition regulation of blood volume/pressure regulation of blood pH conservation of valuable nutrients production/secretion of hormones assist the liver is detoxification eliminate organic wastes and foreign substances *nitrogenous waste
What three things describe the overall function of the urinary system
filtration of cellular wastes from blood
selective reabsorption of water and solutes
excretion of the wastes and excess water as urine
This is where the renal vessels, nerves, and renal pelvis pass into/out of the kidney
hilum
This is filled with loose connective tissue and fat, along with the renal pelvis, the calyces, and branches of vessels/nerves
renal sinus
The kidney surface is covered by what
connective tissue called the renal capsule
This the the functional part of the kidney and it can be divided into two regions
parenchyma
This is the superficial (outer) area of the kidney
renal cortex
This is the deep (inner) area of the kidney
renal medulla
Thee are 6-18 distinct conical or triangular structures of which funnel toward the renal sinus
renal pyramids
This is located between the pyramids; cortical tissue within medulla
renal columns
This is located at the apex of the pyramid and is the main location of urine production
renal papilla
This consists of the renal pyramid, its overlying renal cortex, and one-half of each adjacent renal column; will not see this is the adult
renal lobe
About what percentage of blood flow from cardiac output is going to the kidney
20-25%
These capillaries are associated with convoluted tubules
peritubular capillaries
This (capillary-like) is associated with the nephron loop
vasa recta
This is the fundamental structural and functional unit of the kidney
nephron
How many nephrons are in each human kidney
approximately 1 million
What are the two parts of a nephron
renal corpsucle
renal tubule
This is where the glomerular filtration occurs; located in the renal cortex
renal corpuscle
This is where tubular reabsorption and tubular secretion occurs
renal tubule
The nephron plus its collecting tubule forms what
uriniferous tubule
In order for urine to be produced, the nephron performs these three processes
glomerular filtration
tubular reabsorption
tubular secretion
This is the first step in urine production; water and most solutes in blood plasma move from the glomerular capillaries into glomerular (Bowman’s) capsule
glomerular filtration
Filtered fluid moves through the renal tubule; and the tubule cells reabsorb 99% of the filtered water and many solutes, they return to the blood at peritubular capillaries
tubular reabsorption
This is when the tubule cells can remove additional substances (wastes, drugs, ions, etc.) from the blood in peritubular capillaries
tubular secretion
What is the main function of the nephron filtration
help maintain homeostasis of blood’s volume and composition
What are the two components of the renal corpuscle
glomerulus
Bowman’s capsule
This is a tuft of capillaries composed of 10-20 capillary loops supplied by an afferent arteriole and drained by efferent arteriole
glomerulus
This is a double-walled epithelial cup surrounding the glomerulus
visceral = inner
parietal = external
Bowman’s (glomerular) capsule
Glomerular ultrafiltrate is collected where before it drains into the renal tubule
The urinary/Bowman’s/capsular space located between the two layers
The visceral layer of Bowman’s capsule contains what type of epithelium
modified simple squamous epithelial cells called podocytes
Extensions of podocytes are called what, which wrap around the single layer of endothelial cells
pedicles
This is the space between two pedicles where the ultrafiltrate from the blood (via fenestrations) enters Bowman’s space
filtration slit
This semipermeable membrane covers the filtration slit
slit diaphragm
The parietal layer of Bowman’s capsule contains what type of epithelium
simple squamous epithelium
This is where afferent and efferent arterioles enter/exit
vascular pole
This is where filtrate exits Bowman’s space and enters PCT
urinary or tubular pole
This attaches to the glomerular capsule; highly coiled tube; lies in renal cortex
proximal convoluted tubule
This extends from the renal cortex into the renal medulla, turns, and returns to cortex
loop of Henle
This is the last part of the renal tubule; highly coiled; lies within renal cortex; empties into a collecting tubule
distal convoluted tubule
The PCT and DCT are lined with what type of epithelium
simple cubodial epithelium
True or False
The PCT contains a lot of mitochondria
True; stains a little pinker and is larger than DCT
The PCT contains what the of border
brush border; microvilli with varying lengths
The loop of henle contains what four parts
thick descending limb
thin descending limb
thin ascending limb
thick ascending limb
What types of epithelium do the thick and thin limb of the loop of henle contain
thick; simple cubodial
thin; simple squamous
True or False
The microvili of the DCT are few and short, therefore the lumen is smoother
True
This is where the ascending limb of the loop of henle contacts the afferent arteriole
macula densa
What becomes of the epithelium at the macula densa
It becomes columnar with apical nuclei
These are the smooth muscle cells located alongside the macula densa
juxtaglomerular cells
The macula dense plus the JA cells form what
the juxtaglomular apparatus (JGA)
What is the function of the JGA
to regulate blood pressure within the kidneys
Several collecting ducts merge at the apex of the pyramid to form what
the papillary ducts (ducts of Bellini) with drain into minor calyx at renal papilla
Papillary ducts are made up of what type of epithelium
simple columnar duts
How man major/minor calices are there
6-8 minor
3-4 major
This is located closer to the pyramid, long nephron tube, concentrated urine
juxtamedullary nephron
This is located further away from the pyramid, small nephron loop, in cortex
cortical nephron
This is a muscular tube about 10-12in in length; uses peristalsis
ureter
This is a hollow, distensible, muscular organ in pelvis; store urine
urinary bladder
This is a tubular structure for the passage of urine from the bladder to the outside of the body
urethra
What is the length of the urethra in males/females
males; 20cm
femals; 3-5cm
True or False
The calyces, renal pelvis, ureter, and urinary bladder have the same basic histological structure with walls becoming thinner close to the bladder
False; the become thick toward bladder
What are the epithelium of the bladder
transitional epithelium (urothelium)
How many layers of muscularis externa (detruser muscle) does the bladder contain
3; inner longitudinal
outer circular
outermost longitudinal
What are the regions of the male urethra
prostatic
membranous
spongy
What epithelium lines the male urethra
prostatic; urothelium
membranous; stratified columnar
spongy; stratified columnar
What epithelium lines the female urethra
stratified squamous; occasionally pseudostratified columnar