Urinary System I Flashcards
Although a great deal of waste material is discarded by the intestines, most was never
truly within the body. Almost all of the waste products originating from within the body itself
are removed and discarded by the _____.
kidneys
The kidneys play a major role in _____ by sorting useful and necessary molecules from
those that are toxic or unneeded.
waste removal
Urine is usually _____ but the pH can vary from ~4.5 to ~8.0 in response to changes in
metabolism or diet.
slightly acidic
Urine composition is complex, but includes ions, _____ from catabolism of amino acids,
_____ from catabolism of dietary nucleic acids and RNA, _____ from decomposition of
creatine in the muscles and the yellow _____ from heme breakdown.
urea; urate OR uric acid;
creatinine; urobilins OR
urochrome
Excessive plasma concentrations of organic molecules (such as glucose) can overwhelm
the kidney’s transport proteins and result in _____.
the presence of organic
molecules in the urine
Damage to the structures of the urinary system from injury or infection can result in the
presence of _____, _____ or _____ in the urine.
large molecules; formed
elements; cells
In a healthy individual, urine is a(n) _____ liquid until it leaves the body, at which time
bacteria present on the external genitalia may contaminate it.
sterile
Kidneys regulate blood _____ and _____ by altering the concentration of the urine (and
thus, the amount of water lost or conserved) and by releasing _____.
volume; pressure; renin
By changing the amount of each ion which is conserved or discarded, the kidneys
indirectly regulate the concentrations of solutes in the _____.
blood OR body
By alternating between direct disposal of urea and disposal of ammonia, and also by
selectively secreting hydrogen or bicarbonate ions, the kidneys have a major influence on
the body’s _____.
pH
By monitoring their own oxygen supply and responding (if low) by releasing _____, a
hormone, the kidneys regulate _____.
erythropoietin; red blood cell
synthesis
The kidneys help to control bone density by regulating the disposal of, or conservation of,
_____ in response to _____.
calcium; parathyroid hormone
The kidneys help to control calcium absorption by regulating the conversion of vitamin D
to _____, which is done in response to _____.
its active form; parathyroid
hormone
Urine is formed by each of two _____. From each, a muscular tube called the _____
propels urine to the _____ where it is stored until its release is convenient, at which time it
flows out of the body through the _____.
kidneys; ureter; bladder; urethra
The kidneys are _____ to the peritoneum. Each lies in the _____ region, anterior to the
_____, but the right is slightly lower than the left to make room for the _____.
posterior; upper lumbar; 12th
rib; liver
The kidneys are encased in a fibrous layer of connective tissue called the _____.
renal capsule
The kidneys are surrounded by an outer fibrous layer called the _____ which _____. This
layer surrounds the adrenal glands as well.
renal fascia; fastens the kidney
to surrounding structures
A dense layer of adipose tissue called the _____ lies between the renal capsule and the
renal fascia. Its function is to _____ and _____ the kidneys.
adipose capsule; support;
cushion
The medial surface is concave and has a(n) _____, where the ureters, blood vessels,
nerves, and lymphatics enter or leave the kidney.
hilus OR hilum
The hilus is continuous with the _____, a much deeper indentation filled with fat which
cushions the structures which enter and leave the kidney.
renal sinus
The outer layer of the kidney, just deep to the renal capsule, is the _____. Columns of
tissue from this region called _____ extend toward the hilus; it is within these columns that
those renal blood vessels having the largest diameter lie.
renal cortex; renal columns
The renal cortex surrounds the _____; columns of cortical tissue extend toward the hilus,
separating it into distinct regions called _____.
medulla; renal pyramids
Each renal pyramid and the cortical tissue surrounding it is called a(n) _____. The term
‘_____’ refers to these units.
renal lobe; lobar
Each renal pyramid is striated. The striations extend from the hilus toward the cortex and
are called _____. (They are actually _____.)
medullary rays; collecting ducts
Each renal pyramid projects into a tube within the renal sinus which conducts urine away
from the kidney. The projection itself is called the _____; the tube which it enters is called
a(n) _____ (the plural is ‘:_____’).
renal papilla; minor calyx; minor
calyces
Several minor calyces merge to form a(n) _____
major calyx
Each kidney contains roughly _____ minor calyces and _____ major calyces.
10-20; 2-3
The major calyces in each kidney merge to form a funnel-like chamber called the _____,
which later narrows to form the _____, which conducts urine to the urinary bladder.
renal pelvis; ureter
Blood (1/4 of the blood pumped by the heart, when one is resting) reaches the kidneys via
the _____, which branch to form _____ which branch again within the renal sinus to form
the _____.
renal arteries; segmental
arteries; lobar arteries
Most of the blood reaching the kidney flows to the _____, where it will be filtered.
renal cortex
Blood flows to the renal cortex through the _____ arteries, then arches around the renal
lobes just below the cortex via the _____ arteries. Many small arteries called the _____
arteries arise here: these supply blood to the _____ arterioles and _____.
interlobar; arcuate; interlobular;
afferent; glomerulus
Blood leaves the glomerulus via the _____, which take it to a second capillary bed, the
_____.
efferent arterioles; peritubular
capillaries