The Urinary System Flashcards
What does the hilum contain?
Renal vessels, nerves, and the renal pelvis
What constitues a lobe?
A medullary pyramid and the overlying cortex plus 1/2 of the renal columns on each side of the pyramid
What is a calyx?
Extensions of the renal pelvis
How man renal papillae does a minor calyx surround?
One
What is the functional unit in the kidney and what does it consist of?
Nephron - renal corpuscle and tubule
What are the four major segments and their components?
Proximal thick segment - PCT and PST
Thin segment - Thin limb (TL)
Distal thick segment - MTAL and CTAL
Distal Convoluted Tube (DCT)
What segments make up the Loop of Henle?
PST, TL, and MTAL
What is the division point between proximal and distal nephron?
Macula densa (Herron)
What are the openings from the renal papilla into the minor calyces termed?
Ducts of Bellini
Is the afferent or efferent arteriole larger?
Afferent
What are the two layers of Bowman’s capsule and their cellular composition
Visceral - Podocytes
Parietal - Simple squamous epithelium
What is the space between the visceral and parietal layers of Bowman’s capsule?
Urinary space
What cells are distributed amongst capillaries in the glomerulus and what is their function?
Mesangial cells - phagocytose debris, provide structural suport, repair (IL1 & PDGF)
What are the subdivisions of the cortex?
Cortical labyrinths and medullary rays
What does a cortical labyrinth consist of?
Renal corpuscles, PCT and DCT
What does a medullary ray consist of?
Straight tubules and collecting ducts
What does a lobule consist of?
A medullary ray and adjacent one-half labyrinths
What does the medulla consist of?
PST, thin limb, and DST
Name arterial vasculature from renal artery to efferent arteriole.
Renal Artery - Lobar Arteries - Interlobar Arteries - Arcuate Arteries - Interlobular Arteries - Afferent Arterioles - Glomerulus - Efferent Arteriole
What do efferent arterioles produce in cortical and juxtamedullary glomeruli?
Cortical - peritubular capillaries
Juxtamedullary - vasa recta (arteriole recta)
What artery is present at the corticomedullary junction?
Arcuate artery
What artery is present at the medullary ray boundary?
Interlobular artery
Where does MOST reabsorption take place?
PCT
Where does MOST secretion take place?
Thin limb, distal tubules, and collecting ducts
What does the juxtaglomerular apparatus consist of?
Macula densa, juxtaglomerular cells, and extraglomerular mesangial cells
What does the juxtaglomerular apparatus do?
Regulate blood pressure
What do macula densa cells do?
Monitor blood volume and [Na]
What do juxtaglomerular cells do?
Secrete renin when stimulated by macula densa cells
Name the route of discharge of urine from collecting ducts to bladder.
Collecting Ducts - Ducts of Bellini - Minor Calyx - Major Calyx - Renal Pelvis - Ureter - Bladder
What cell type lines the excretory passages?
Transitional epithelium
*Note the lower part of the urethra has stratified or pseudostratified columnar epithelium
What is the general structure of excretory passages?
Mucosa, muscularis, and adventitia (serosa)
*Note except urethra
How many muscle layers in ureter and bladder?
Upper Ureter - 2
Lower Ureter - 3
Bladder - 3
(Inner longitudinal, Middle circular, Outer longitudinal)
