Urinary Test Flashcards
What are the components of the urinary system?
Kidneys, ureters, bladder, urethra
What three processes occur in the nephron?
Glomerular filtration, tubular reabsorption, and tubular secretion
What are the intrinsic controls of GFR?
Renal auto-regulation, myogenic controls, tubuloglomerular feedback mechanism
Where does GFR take place?
The nephron
What do myogenic controls do?
They intrinsically control glomular pressure, the constriction of muscles via blood pressure, and responses to stretch
What controls glomular pressure?
Myogenic responses
What does the tubuloglomerular feedback mechanism of the GFR do?
It releases vasoconstricting chemicals, constricts afferent arteries, and slows GFR to allow time for filtration
What releases vasoconstricting chemicals?
The tubuloglomerular feedback mechanism
What is GFR in charge of?
Net filtration pressure
What are the extrinsic controls of the GFR?
Sympathetic nervous system and the renin-angiotensin mechanism
What does the sympathetic nervous system of the GFR do?
It overrides intrinsic controls during emergency, and causes the vasoconstriction of arterioles via (nor)epinephrine
What does the renin-angiotensin mechanism of the GFR do?
It releases renin, which results in angiotensin II release
What does the release of angiotensin in the GFR do?
It’s a vasoconstrictor that aids in the reabsorption of sodium, stimulates the release of ADH & activates thirst, and decreases pertibular capillary pressure
What makes up the tubuloglomerular feedback mechanism?
Macula densa cells
What is generally fully absorbed?
Glucose, amino acids, lactate, and uric acid
Where does reabsorption occur?
The nephron
What should urine not contain?
Glucose, amino acids, lactate, and uric acid
What are the two types of nephrons?
Cortical and juxtamedullary
What are the features of cortical nephrons?
They make up most nephrons and they’re shorter + more winding and make up pertibular capillaries
What are the features of juxtamedullary nephrons?
They’re longer + less winding, extend much further into medullar, vasa recta, and concentrated urine formation
What is renal clearance?
The volume of plasma cleared of a substance in a minute
Where does water leave the nephron?
The descending limb
Where does salt leave the nephron?
The ascending limb
Where is the vasa recta?
Near the nephron
What process requires ATP?
Removing salt from the nephron
Why is sodium important for the kidneys?
The kidneys need it to bond with chloride to form salt so it can be removed on the ascending limb
What molecule does ADH affect and in what way?
ADH affects the reabsorption of water in collecting ducts
What does the vasa recta do?
It preserves the osmotic gradient by removing water and solutes
What part of the nephron is in charge of filtration?
The glomerulous
What part of the nephron is in charge of absorbing glucose and amino acids?
The proximal convoluted tubule
What does the proximal convoluted tubule do?
It absorbs glucose and amino acids
What part of the nephron is in charge of sodium and calcium regulation?
The distal convoluted tubule
What part of the nephron is in charge of reabsorbing water, sodium, urea, and hydrogen?
The collecting duct
What is controlled by aldosterone?
The regulation of sodium
What is controlled by ADH?
Urea reabsorption
How do the ascending and descending tubules work?
The ascending lets salt out which means we can take water out through the descending
What does the vasa recta do?
It maintains balance by its blood absorbing salt and water
What does the osmolality of the medulla and cortex look like?
The middle is 1200, and the cortex is 300
What does blood have to go through to pass through the nephron?
Aorta, renal artery, segmental artery, interlobular artery, arcurate artery, cortical radial artery, afferent arteriole, glomerulus, efferent, pertibular capillaries/ vasa recta
