Urinary system chapter 26 Flashcards
What are the components of the urinary system?
Kidneys, ureters, urinary bladder, urethra
On average, how much urine can the urinary bladder hold?
700-800 mL
What is the micturition reflex?
the act of emptying the bladder
What are the components of the male urethra?
prostatic, membranous, spongy
What are the functions of the kidneys?
remove substances from blood, form urine, regulate metabolic processes
What constitutes the renal corpuscle?
glomerulus, glomerular capsule, afferent arterioles, efferent arterioles
What constitutes the renal tubule?
proximal convoluted tubule, nephron loop, distal convoluted tubule
What is meant by glomerular filtration?
forces filtration of waste-lade blood into the glomerulus
What is meant by tubular reabsorption?
the process of returning important substances from the filtrate back into the body
What is meant by tubular secretion
the movement of waste materials from the body to the filtrate
What makes up the glomerular filtrate?
same composition as blood plasma minus the plasma proteins
Explain glomerular capillary hydrostatic pressure
the pressure exerted by the blood from entering into the capillaries, it pushes fluid out of the capillary network and into the capsule
Explain glomerular capillary osmotic pressure
pulls water back into the capillary due to plasma proteins in the blood
Explain capsular hydrostatic pressure
pushes water back into capillaries due to the expansion of the capsule
What is the GFR?
blood hydrostatic pressure - blood osmotic colloid pressure - capsular hydrostatic pressure
How does vasoconstriction affect the GFR?
decreases GFR
How does vasodilation affect the GFR?
increases GFR
What happens to GFR when BP drops?
it decreases
How does the kidney auto-regulate the GFR?
it constricts and dilates the afferent arterioles
How does the sympathetic impulses affect the GFR?
releases norepinephrine causing constriction of the afferent arterioles
How does Angiotensin II affect GFR and/or urine formation?
Angiotensin II is a vasoconstrictor, decreasing GFR and urine formation
How does aldosterone affect GFR and/or urine formation?
causes the retention of sodium, therefore retention of water; decreases urine formation
How does ANP affect GFR and/or urine formation?
released by the atria of the heart, causes the glomerulus to relaxes, decreasing the capsular pressure, increasing GFR/urine production
How does ADH affect GFR and/or urine formation?
causes collecting duct to become more permeable to water, allowing the body to retain more water, decreasing urine production
What is meant by tubular reabsorption?
process of returning important substances from the filtrate back into the renal blood vessels
Where does most reabsorption take place?
proximal convoluted tubule
Define isotonic.
equal concentrations of solute and water
Define hyptonic
less solute, more water
define hypertonic
more solute, less water
What is tubular secretion
movement of substances from the capillaries which surround the nephron into the filtrate
What are the components of urine?
water, urea, uric acid, creatinine
What is the normal amount of urine excreted by the horus?
50-60 mL
What amount of urine per hour might indicate kidney failure?
<30mL/hr
What does BUN mean and what does it measure?
Blood urea nitrogen, measures nitrogen wastes in blood from catabolism and deamination of amino acids
How does creatinine clearance test help determine GFR?
measures the amount creatinine in the blood, which increases in states of renal dysfunction
af-
to
glom-
little ball
juxta-
near to
calyc-
small cup
mict-
to pass urine
detrus-
to force away
cort-
covering
papill-
nipple
nephr-
pertaining to the kidney
cyst-
bladder
ren-
kidney
trigon-
triangular shape
prox-
nearest
