Kidney Structure
The uretur.
Optimal blood pH.
7.3 - 7.4.
The four major steps of urine formation.
Pressure filtration, selective reabsorption, water reabsorption and tubular secretion.
Why is the ascending side of the LoH impermeable to H2O?
Otherwise it would allow the H2O reabsorbed in the descending side to return to the filtrate.
Initiator of ADH secretion.
Osmoreceptors in the hypothalamus detect low H2O levels in blood.
List the wastes secreted by the kidney.
Nitrogenous wastes such as urea and ammonia, uric acid(nucleotide metabolism) and creatinine from muscles.
In a healthy person, the collecting duct is found in the renal _____.
Renal medulla, draining into the renal pelvis.
H2O reabsorption mostly occurs in the PCT. True or false?
True. The loop of Henle and collecting duct reabsorb H2O, but considerably less.
Selective reabsorption is done by active transport. True or false?
False. Passive transport of H2O, Cl and urea(small amount) occurs as well (in the first half of the PCT).
Source of aldosterone.
A high protein diet.
High amounts of cilia and mitochondria are present in the PCT. True or false?
False. High amounts of mitochondria and microvilli to facilitate active transport.
Where in the nephron would histamines be secreted?
DCT by tubular secretion.
How a high salt diet will affect blood pressure.
High salt intake leads to more salt in blood = more H2O being reabsorbed = higher BP.
The permeability of the DCT and collecting duct is affected by secretions from this structure.
More aquaporins open due to ADH released from the posterior pituary gland.
The four major components of the kidney.
Renal cortex, medulla, pelvis and individual nephrons.
What could cause high levels of proteins to be present in the urine?
Difference between the descending and ascending side of the loop of Henle.
The descending side increases in hypertonicity as it goes down to reabsorb H2O, the ascending side actively transports Na+ to create such conditions.
Why does blood that is excessively acidic will lead to urine with a low pH?
More H+ ions will be secreted into the filtrate in the DCT so the resulting urine will be acidic.
The effect of alcohol on blood pressure.
Inhibits ADH secretion, H2O is not reabsorbed so blood pressure decreases.
The order of structures urea travels through in the nephron, starting at the renal artery.
Renal artery > afferent arterioles > glomerulus > glomerular(Bowman's capsule) > PCT/peritubular capillary network > loop of Henle > DCT > collecting duct > renal pelvis.
Describe the function of the PCT.
The PCT actively transports glucose, AAs, Na+, passively H2O, Cl- and urea. Has lots of microvilli and mitochondria; selective reabsorption.
Describe the ratio of amino acids in the renal artery vs. the renal vein.
Renal vein would have less because the cells in the kidney need to use the amino acids.
List 4 particles present in the afferent arteriole, but not the efferent arteriole.
Glucose, ions, amino acids, urea and H2O.
Explain why K+ is secreted when low Na+ levels are detected in the blood.
Functions in the Na+/K+ pump to move Na+ into the blood and K+ out, raising Na+ levels.