Kidney Flashcards
What is the urinary system consists of and function
Kidney, ureters, urinary bladder and urethra
Remove waste products of metabolism by urine
What shape is the kidney and what is it function
PAIRED bean shaped organ
12-cm long, 6-cm wide, and 2.5-cm thick
in adults
Excretory and endocrine function to maintain homeostasis
Situated in retroperitoneal space at level of 12th thoracic and 1-2 lumbar vertebrae
What does each kidney consist of and what is its major fuctional unit
Parenchymal organ
Cortex, medulla, calyces
nephron main unit
What is the outer layer of kidney, the medial border and lateral surface
Outer layer enclosed by connective tissue and adipose tissue
Concave Medial margin= renal hilum which is continuous woth renal sinus.Nerves enter, the ureter exits, and blood and
lymph vessels enter and exit
Concave lateral surface= covered by connective tissue capsule
What does renal medulla contain (inner)
7-18 renal pyramids- base facing cortex, apical to renal sinus
Each pyramid plus the cortical tissue at its base and extending along its sides constitutes a renal lobe.
Medullary rays formed by parallel ducts and tubules from medulla to cortex
. The tip of each pyramid, called the renal
papilla, projects into a minor calyx that collects urine formed
by tubules in one renal lobe.
Contains the tubules and the collecting ducts of the nephron
What does renal cortex contain (outer)
Situated between renal capsule and bases of the pyramids
Darker than medulla bc receives 90% of kidney blood supply
Contains the renal corpuscles and convuluted tubules of nephrons
What are calyces
Calyces gradually increase in size, starting with the minor calyces, which open into larger major calyces, which empty into the renal pelvis.
From the renal pelvis, the urine passes into the ureter.
The portion of the kidney which contains the calyces, renal pelvis, ureter and renal vessels is called the renal sinus.
What does nephron consist of
Renal corpuscle, tubules, single layer of epithelial cells on basal lamina
What is the renal corpuscle
Function is to filter blood
In cortex= glomerulus + Bowmans capsule
GLOMERULUS: capillary tuft origin afferent arterioles which merge to form efferent arterioles
BOWMANS CAPSULE: parietal layer with simple squamous and visceral layer with PODOCYTES. Urinary space os the space between these layers where primary urine enters from glomerular filtration
Has vascular pole- afferent and efferernt arteries enter/leave glomerulus
Tubular pole-urinary space continuous with PCT
What are the system of tubules in nephron
PROXIMAL TUBULES= long convoluted part in cortex, straight part enters the medulla
LOOP OF HENLE= descending and ascending portions in medulla
DISTAL TUBULES= convulted in cortex regulated by ADH and aldosterone, straight in medulla/cortex
COLLECTING DUCT= From collecting tubules. They merge into papillary ducts (at renal pyramids) Each collecting ducts and all the nephrons that drain into it forms the RENAL LOBULE
Difference between Cortical nephrons and Juxtamedullary
Cortical= Corpuscles in outer cortex and short loop of henle
Juxtamedullary= Corpuscles below renal pyramid, close to corticomedullary border and long loop of henle
Difference between the proximal tubules and distal tubules
PCT has microvilli which is why it is stained more pink with eoisin in the slides
How is blood filtered by renal corpuscles
*Through urinary space, primary urine is received
- Glomerulus filtration barrier= basal lamina (glomerular basement membrane), fenestrated endothelium, podocytes (visceral layer)
- podocytes have processes called pedicles. There are filtration slits between these (made of nephrins)
- the GBM is between the endothelial and podocytes and prevent larger proteins passing through
What is the permeability of the components of the glomerulus filtration barrier
fenestrated endothelium>Basal lamina> filtration slits
The fenestrations of the capillary endothelium, which
blocks blood cells and platelets
■ The thick, combined basal laminae, or GBM, which
restricts large proteins and some organic anions
■ The filtration slit diaphragms between pedicels, which
restrict some small proteins and organic anions
What are the glomerular capillary tufts lined with if not covered by podocytes
irregularly shaped MESANGIAL CELLS
Contractile, endocytic and phagocytic activiteis
