Urinary system Flashcards
What is the composition of the filtrate in the capsular space?
Similar to plasm, only no proteins
What part of the nephron is involved with obligatory water, ion, and organic nutrient reabsorption?
PCT
Why don’t plasma proteins pass in tot he capsular space under normal circumstances?
Glomerular capillary pores are too small
What is the major driving force behind filtrate production?
Hydrostatic pressure in the afferent arteriole
Why are glomerular pressures higher than pressure in other capillaries?
The efferent arteriole has a smaler diameter than the afferent arteriole, increasing resistance.
What effect does renin have on the glomerular filtration rate (GFR)?
It will increase the GFR and vasoconstrictor the efferent arteriole.
Why is the presence of microvilli important to the epithelial tissue of the PCT?
Because most reabsorption occurs at the PCT
Why does the filtrate dilute all along the ascending loop?
A glycoprotein here restricts water from leaving the filtrate
A decrease in Na+ in the blood leads to an increase in blood pressure because?
It increases aldosterone secretion. It increases renin production. It increases ADH secretion.
Why does osmotic concentration decrease in the thick ascending limb of the nephron loop?
Na+ and CI- are actively transported out of the tubular fluid.
Which structures exit at the hilum of the kidney?
A renal artery and vein. Renal ureters.
An obstruction of a ureter by a kidney stone limits the flow of urine between which two points?
Renal pelvis and urinary bladder
The ability to control the micturition reflex depends on the ability to control which muscle?
External urinary sphincter
Mary has had a urinalysis that indicated a high level of bilirubin. What condition may she have?
Liver disease
What effect does eating a high-protein diet have in the composition of urine?
Increased urea. Increased fluid volume.
Which portion of a nephron is NOT in the renal cortex?
Nephron loop
Damage to which part of the nephron interferes with hormonal control of blood pressure?
Juxtaglomerular
What event occurs when the plasma concentration of a substance exceeds its tubular maximum?
Excess is excreted in urine
How would the absence of juxtamedullary nephrons affect the volume of urine and its osmotic concentration?
Increase volume; decrease osmotic concentration
The concentration of filtrate is greatest in____. This is because__.
The bottom of the nephron loop; solutes are concentrated
Where does urine production begin?
Nephron
How are cortical and juxtamedullary nephrons structurally different?
Juxtamedullary nephrons have longer nephron loops.
What effect does an increased amount of aldosterone have on K+ concentration of urine?
K+ Increases
All of the following EXCEPT___ are effects of angiotensin 2?
Inhibition of ADH release
What is the role of the vasa recta in the urinary system?
Returning water and solutes to general circulation
What direct effect sympathetic activation have on GFR?
Produces powerful vasoconstriction of the afferent arteriole
