1st year revision Flashcards
(24 cards)
Which kidney is cranial?
Right
Where in the body are the kidneys located?
Dorsal abdomen
What is the hilus?
Where the renal artery, vein, lymphatics and nerves enter and exit the kidney
What are the 3 layers of the kidney?
- Capsule
- Cortex
- Medulla
What % of the cardiac output do kidneys recieve?
20-25%
Describe the branching of arteries in the kidney
- Renal arteries branch into 6-8 interlobar arteries
- These branch to form arcuate arteries and the corticomedullary junction
- These branch into interlobular arteries which become afferent arterioles
Where does ultrafiltration of plasma occur?
Glomerulus, through pores in the glomerular capillary wall into the Bowman’s capsule
In the PCT what remains in the filtrate
Proteins
What is the function of the loop of Henle?
- Acts as a countercurrent multiplier
- generates medullary hypertonicity
- Selective reabsorption of various solutes and secretion of substances occurs to regulate the final excretory product
Which molecule controls permeability of the DCT and CD to water?
ADH
Give examples of roles of the kidney
- Fluid and electrolyte homeostasis
- Nitrogenous waste excretion
- Acid/base homeostasis
- Synthesis of calcitriol
- Erythropoietin production
- BP homeostasis
- Renin production
Where does urine pass to enter the ureters?
From the collecting ducts into the renal pelvis
What cells line the bladder?
Transitional epithelium
What are the 3 parts of the urethra in the male?
- Prostatic portion
- Pelvic portion
- Cavernous portion
What cells line the urethra?
Transitional epithelium
- except for the terminal part in males which is lined by stratified squamous epithelium
Give a definition of GFR
The total volume of fluid filtered by all of the glomeruli in both kidneys per unit time.
GFR is proportional to the number of functioning nephrons which is proportional to the functional renal mass.
How many times per day is the entire plasma volume filtered?
50
What is a high GFR required for?
To effectively remove wastes from the body and regulate fluid & electrolyte balance.
What are the 2 main factors affecting GFR?
- Differences in hydrostatic pressure across the filter
- Differences in protein- osmotic pressure across the filter
How is GFR affected if renal blood flow decreases?
Decrease in GFR
- A larger fraction of plasma can be filtered out of the capillaries leading the inward protein-oncotic pressures balancing out the hydrostatic pressures before the end of the glomerular capillaries
What is azotaemia?
an abnormal concentration of urea, creatinine and other nitrogenous compounds in the blood
When does azotaemia occur?
When GRF is decreased/urine is retained
What does renal azotaemia result from?
Renal parenchymal disease
Why does pre-renal azotaemia occur?
Following a loss of renal function due to reduced renal perfusion e.g. dehydration, hypovolaemia, heart failure
