Urinary System Flashcards
Approximately 12-cm long, 6-cm wide, and 2.5-cm thick in adults,
KIDNEYS
has an outer renal cortex, a darker stained region with many round corpuscles and tubule cross sections,
Parenchyma
an inner renal medulla consisting mostly of aligned linear tubules and ducts, which consists of 8-15 conical structures called
renal pyramids
all with their bases meeting the cortex (at the corticomedullary junction) and separated from each other by extensions of the cortex called
renal columns
Each pyramid plus the cortical tissue at its base and extending along its sides constitutes a
renal lobe
The tip of each pyramid, projects into a minor calyx that collects urine formed by tubules in one renal lobe
renal papilla
Each kidney contains 1-4 million functional units called
nephrons
each consisting of a corpuscle and a long, simple epithelial renal tubule with three main parts along its length
NEPHRON
Initial dilated part enclosing a tuft of capillary loops and the site of blood filtration
RENAL CORPUSCLE
Location of the Renal Corpuscle
Cortex
Glomerulus
Bowman’s capsule
a long convoluted part, located entirely in the cortex, with a shorter straight part that enters the medulla.
PROXIMAL TUBULE
Nephron Loop
LOOP OF HENLE
in the medulla, with a thin descending and a thin ascending limb.
LOOP OF HENLE
consisting of a thick straight part ascending from the loop of Henle back into the cortex and a convoluted part completely in the cortex.
DISTAL TUBULE
a short minor part linking the nephron to collecting ducts
CONNECTING TUBULE
In the glomerulus, where the blood enters
Afferent arterioles
In the glomerulus, where the blood exits
Efferent arteriole
What is the epithelial tissue of the Glomerulus
Stratified squamous epithelium
What type of capillaries are there in the Glomerulus?
Fenestrated capillaries
What is the epithelium of the Bowman’s capsule?
Simple squamous epithelium
What type of capillaries are there in the Bowman’s capsule?
Fenestrated capillaries
It has podocytes
Bowman’s capsule
RENAL FUNCTION:
FILTRATION
TUBULAR SECRETION
TUBULAR REABSORPTION
RENAL FUNCTION:
Water and solutes
FILTRATION
RENAL FUNCTION:
From blood vessels to tubular lumen
FILTRATION
TUBULAR SECRETION
RENAL FUNCTION:
by which water and solutes in the blood leave the vascular space and enter the lumen of the nephron.
FILTRATION
RENAL FUNCTION:
From blood vessels to tubular lumen
FILTRATION
TUBULAR SECRETION
RENAL FUNCTION:
by which substances move from epithelial cells of the tubules into the lumens, usually after uptake from the surrounding interstitium and capillaries.
TUBULAR SECRETION
RENAL FUNCTION:
From tubular lumen to blood vessels
TUBULAR REABSORPTION
RENAL FUNCTION:
by which substances move from the tubular lumen across the epithelium into the interstitium and surrounding capillaries
TUBULAR REABSORPTION
At the beginning of each nephron is a renal corpuscle, about 200 μm in diameter and containing a tuft of glomerular capillaries, surrounded by a double-walled epithelial capsule called the
glomerular (Bowman) capsule
forms the surface of the capsule
parietal layer
Between the two capsular layers is the _________, which receives the fluid filtered through the capillary wall and the visceral layer
capsular (or urinary) space
The visceral layer of a renal corpuscle consists of unusual stellate epithelial cells called
podocytes
From the cell body of each podocyte, several ______ extend and curve around a length of glomerular capillary
primary processes
Each primary process gives rise to many parallels, interdigitating secondary processes or _______. The _____ cover much of the capillary surface, in direct contact with the basal lamina.
pedicels
What is the epithelium of the Proximal Convoluted tubule?
Simple cuboidal epithelium
Where is the Proximal Convoluted Tubule located?
Cortex
Reabsorption of all organic nutrients, all proteins, most water, and electrolytes
PROXIMAL CONVOLUTED TUBULE
Secretion of organic anions and cations, H+, and NH4+
PROXIMAL CONVOLUTED TUBULE
Loop of henle:
- Thin Limbs (Ascending & Descending)
- Thick Ascending
What is the epithelium of the Thin Limbs (Ascending and Descending) of the Loop of Henle?
Simple squamous epithelium
What is the epithelium of the Thick Ascending of the Loop of Henle?
Simple cuboidal epithelium
Both the Thin Limbs and Thick Ascending is located at the
Medulla
Passive reabsorption of Na+ and Cl
Thin Limbs (Ascending & Descending)
Active reabsorption of various electrolytes
Thick Ascending
What is the epithelium of the Distal Convoluted Tubule?
Simple cuboidal epithelium
Reabsorption of electrolytes
Distal Convoluted Tubule
