Anatomy of the Renal System Flashcards
What are the basic functions of the renal system?
Filter blood plasma to remove waste Regulate blood volume and pressure Regulate electrolyte balance Regulate body fluid PH Regulate RBC count Contribute to calcium homeostatis Detoxify Free Radicals and some drugs Carry out gluconeogensis for starvation
What are the 6 organs of the renal system?
Kidneys R+L
Ureters R+L
Urinary bladder
Urethra
Where is the kidney located in the body?
Between peritoneum and retroperitoneal space
What does the concave medial border of the kidney face?
vertebral column
Upper with T12
Lower with L3
Which ribs partially protect the kidneys?
11th and 12th ribs
Right is lower than left due to liver
What are the vital stats for kidneys?
130-160g
10-12cm long
5-7cm wide
3cm thick
What are the 3 layers surrounding the kidney?
Renal capsule
Adipose Capsule
Renal fascia
Describe the renal capsule?
Deep Layer Smooth Dense irregular CT continous with ureter Trauma barrier Maintains shape
Describe the Adipose capsule?
Middle
Fatty tissue
Trauma barrier
maintains position
Describe the Renal fascia?
Superficial layer
Dense Irregular CT
anchors kidney to abdominal wall
What is the Renal Parenchyma?
Renal cortex - superifical, smooth, brown
Renal medulla - deep, striated, Reddish
What is the renal sinus?
Anything thats not cortex or medulla (inside)
What does a renal lobe consist of?
1 renal pyramid
Overlaying area of renal cortex
1/2 adjecent renal column
What is the blood supply to the kidneys?
0.5% body mass
20-25% CO
Via L+R renal arteries from abdominal aorta
complex path of blood through kidney
What is the blood supply starting from the Renal Artery?
Renal Artery - segmental - interlobar - arcuate - interlobular - Afferent Arterioles- Glomerular capillaries - Efferent Arterioles
What capillaries dont drain into a venule? where do they drain instead?
Glomerular - drain into arteriole which drains into capillaries
What are portal vessels?
Efferent arterioles
What is the blood supply starting from the Efferent Arterioles?
Efferent Arterioles - Peritubular capillaries - Interlobular Veins - arcuate - interlobar - segmental - renal vein (i.e Inferior vena cava)
Where do efferent arterioles go to?
Vasa recta (medullary capillaries to interlobular/arcuate veins
Describe the nephron?
Functional unit
each afferent arteriole supplies 1 nephron
Blind ended tubes
2 main: Renal corpuscle and tubule
What are 2 main parts of the renal corpuscle?
Glomerulus
Bowmans capsule
Describe the glomerulus?
Ball of capillaries supplied by afferent arteriole
Initial site of urine production
Drained by efferent arteriole
Inserted into Bowmans capsule like a fist
200 um in diam
Describe the Bowmans capsule?
Site of blind end of nephron
Outer parietal layer continuous with renal tubule
Capsular space (filtrate collects)
Inner visceral layer has podocytes which envelop glomerular capillaries
What is the Renal tubule consisted of?
PCT
Loop of henle
Distal tubule
Collecting duct
What are the 2 types of Nephrons?
Cortical 85% - glomeruli in outer cortex, short loops of henle
Juxtamedullary 15% - glomeruli in inner cortex, long loops of henle deep into medulla
Describe the PCT?
Proximal tubule early part convoluted Late part is striaght (recta) 15mm cuboidal/columnar epithelium
Describe the Loop of henle?
U shaped
descending and ascending limbs
thick and thin segments
Describe thick part of Loop of henle?
Simple cuboidal initial part of descending all or part of ascending has mitochondria metabolically active
Describe the thin segments of the Loop of Henle?
Simple squamous lower of descending limb part of ascending low metabolic activity high permeability to water
What is the juxtaglomerular apparatus?
final part of ascending loop of henle returns to afferent arteriole of same nephron
Macula densa
Juxtaglomerular cells SMC
Describe the DCT?
similiar to thick ascending loop of henle
cuboidal
Late part cuboidal
Has 2 cell types;
- Principal cells ADH and aldosterone receptors
- Intercalated cells - Carbonic anhydrase PH
Describe the Collecting duct?
recieves fluid from 6 distal tubules
In the medulla pair upto form -
ducts of bellini (drain into minor calyx’s)
