Structure and Function of the Kidney and Urinary Tract Flashcards
(95 cards)
Where are the Kidneys located?
In the Retroperitoneum, behind the abdomin, protected by lower ribs
How much blood supply do the kidneys receive from the heart?
~25%
What are the Kidneys function?
- filter blood into urine, excreting waste products
- regulation of water, salt, calcium, phosphorus, blood pH, and others
- Endocrine function: Renin, Erythropoietin, regulates Vitamin D metabolism
How much blood do the kidney’s filter each day?
1700 L per day, to create 1 L of urine
What does Renin do?
regulate blood pressure
What connects the Kidneys to the Bladder?
Ureters
What are the Kidneys supplied by?
The renal artery
What is the outflow of blood from the Kidneys supplied by?
the renal vein
What is the Hilum?
Contains renal artery, renal vein, and ureter
What is the Cortex?
Contains glomeruli and tubules
What is the Medulla?
- Contains collecting system (renal pyramids)
- from which urine drains into renal calyces, renal pelvis, and ureter
What is the Ureter?
a muscular tube that connect the kidneys to and enters the bladder
What is the Bladder?
a hollow organ that is a reservoir for urine
What is the Urethra?
a fibromuscular tube from the bladder to the exterior
What are the main components of the Cortex?
- Glomeruli
- Tubules
- Interstitium
- Blood vessels
What is the Glomerulus? (4)
- A functional unit of filtration
- tuft of capillaries, with afferent (inward) and efferent (outward) arterioles
- Capillaries are lined by glomerular basement membrane (GBM)
- surrounded by double lining of epithelial cells, called Bowman’s capsule
What is the Bowman’s space?
The space between the epithelial layers, also called urinary space
What do the capillary endothelial cells contain?
Fenestrations (sieve-like holes)
What do Fenestrations do?
- allow for passage of fluid and small molecules (water, electrolytes)
- restricts passage of larger molecules (proteins) and blood cells
What surrounds the endothelial cells?
Glomerular basement membrane
What does the Glomerular basement membrane do?
Aids in filtrations, as physical barrier and charge barrier
What are the Glomerular basement membrane and the endothelial cells surrounded by together?
Podocytes, which contain foot processes with filtration silts
Where does blood in the capillary space pass through?
- fenestrations
- glomerular basement membrane
- podocyte filtration slits
What occurs with the left over fluid in the urinary space?
It needs to be concentrated and therefore enters the proximal convoluted tubule