Ch 44 Assessment Of Urinary System Flashcards
2 kidneys and 2 ureters.
upper urinary system consists of
a urinary bladder and urethra
lower urinary system consists of
the kidneys, drains through the ureters to be stored in the bladder, and then passes out of the body through the urethra.
Urine is formed in
(1) regulate the volume and composition of extracellular fluid (ECF) and (2) excrete waste products from the body. The kidneys also function to control BP, make erythropoietin, activate vitamin D, and regulate acid-base balance.
primary functions of the kidneys are to
the kidney and serves as a shock absorber if this area is traumatized from a sudden force or strike.
capsule protects
on the medial side of the kidney serves as the entry site for the renal artery and nerves and as the exit site for the renal vein and ureter.
The hilus
is the actual tissue of the kidney
parenchyma
is the functional unit of the kidney
nephron
the glomerulus, Bowman’s capsule, and a tubular system.
Each nephron is composed of
the proximal convoluted tubule, loop of Henle, distal convoluted tubule, and collecting tubules
tubular system consists of
glomerulus, Bowman’s capsule, proximal tubule, and distal tubule are in the
located cortex of the kidney.
loop of Henle and collecting tubules
are in the medulla.
merge into a pyramid that empties via the papilla into a minor calyx.
collecting ducts eventually
at the level of the twelfth rib, is lower than the left.
right kidney, positioned
thin, smooth layer of fibrous membrane called the capsule covers the surface of each kidney
capsule
the kidney and serves as a shock absorber if this area is traumatized from a sudden force or strike.
capsule protects
on the medial side of the kidney serves as the entry site for the renal artery and nerves and as the exit site for the renal vein and ureter.
hilus
outer layer of the parenchyma is the
cortex
inner layer is the
medulla.
of a number of pyramids
medulla consists
minor calyces widen and merge to form major calyces, which form a funnel-shaped sac called the
renal pelvis.
urine to the renal pelvis, from there it drains through the ureter to the bladder.
minor and major calyces transport
a small volume of urine (3 to 5 mL).
renal pelvis can store
is the functional unit of the kidney
nephron
afferent arteriole divides into a capillary network, the glomerulus, which is a collection of up to 50 capillaries
glomerulus
the outcome of a complex, multistep process of filtration, reabsorption, secretion, and excretion of water, electrolytes, and metabolic waste products.
Urine formation is
to filter the blood and maintain the body’s internal homeostasis.
primary functions of the kidneys are
at the glomerulus, where blood is filtered
Urine formation begins
a semipermeable membrane that allows filtration
glomerulus is
hydrostatic pressure of the blood within the glomerular capillaries causes a portion of blood to be filtered across the semipermeable membrane into Bowman’s capsule.
into Bowman’s capsule.
Filtration is more rapid in the glomerulus than in ordinary tissue capillaries because the glomerular membrane is porous.
glomerular membrane is porous.
that it lacks blood cells, platelets, and large plasma proteins.
glomerular filtrate is similar in composition to blood except
, which allows plasma proteins and blood cells to pass into the urine.
kidney diseases, capillary permeability increases
amount of blood filtered each minute by the glomeruli is expressed as the
glomerular filtration rate (GFR)
about 125 mL/min
normal GFR is
the glomerular filtrate before it reaches the end of the collecting duct. Therefore only 1 mL/min (on average) is excreted as urine.
peritubular capillary network reabsorbs most of
responsible for the reabsorption of essential materials and excretion of nonessential ones
tubules and collecting ducts are
is the passage of a substance from the lumen of the tubules through the tubule cells and into the capillaries
Reabsorption
passage of a substance from the capillaries through the tubular cells into the lumen of the tubule.
Tubular secretion
about 80% of the electrolytes are reabsorbed.
proximal convoluted tubule,
includes all glucose, amino acids, and small proteins reabsorbed
proximal convoluted tubule,
water is conserved, which is important for concentrating the filtrate.
reabsorption continues in the loop of Henle,
is permeable to water and moderately permeable to sodium, urea, and other solutes.
descending loop
chloride ions (Cl−) are actively reabsorbed, followed by passive reabsorption of sodium ions (Na+).
ascending limb,
About 25% of the filtered sodium is
reabsorbed in the ascending limb.
final regulation of water balance and acid-base balance.
Two important functions of the distal convoluted tubules are
permeable to water. This allows water to be reabsorbed into the peritubular capillaries and eventually returned to the circulation.
ADH makes the distal convoluted tubules and collecting ducts
in the anterior hypothalamus detect decreases in plasma osmolality
Osmoreceptors
cells have neuronal axons that end in the posterior pituitary gland and act to inhibit secretion of ADH.
superoptic nuclei
on the distal tubule to cause reabsorption of Na+ and water.
Aldosterone (released from the adrenal cortex) acts
both circulating blood volume and plasma concentrations of Na+ and K+.
secretion of aldosterone is influenced by
reabsorbing and conserving most of the bicarbonate (HCO3−) and secreting excess hydrogen ions (H+).
Acid-base regulation involves
within a range of 7.35 to 7.45
distal tubule has different ways to keep the pH of ECF
, atrial natriuretic peptide (ANP), in response to atrial distention from an increase in plasma volume.
Myocyte cells in the right atrium secrete a hormone
the kidneys to increase sodium excretion
ANP acts on
the adrenal glands, thereby suppressing aldosterone secretion
ANP inhibits renin, ADH, and the action of angiotensin II on
the production of a large volume of dilute urine. ANP also causes relaxation of the afferent arteriole, thus increasing the GFR.
combined effects of ANP result in
in response to low serum calcium levels.
parathyroid gland releases parathyroid hormone (PTH)
serum calcium levels by causing increased tubular reabsorption of calcium ions (Ca2+) and decreased tubular reabsorption of phosphate ions (PO42−)
PTH maintains
will have a deficiency of the active metabolite of vitamin D and problems with calcium and phosphate balance
patient with kidney failure (also called renal failure)
in calcium balance
renal tubules are also involved
in response to low serum calcium levels.
parathyroid gland releases parathyroid hormone (PTH)
serum calcium levels by causing increased tubular reabsorption of calcium ions (Ca2+) and decreased tubular reabsorption of phosphate ions (PO42−).
PTH maintains
cleanse blood plasma of unnecessary substances.
basic function of nephrons is to
the unwanted from the wanted portions of tubular fluid.
After the glomerulus has filtered the blood, the tubules select
is a hormone made in the kidneys and secreted in response to hypoxia and decreased renal blood flow
Erythropoietin
the bone marrow.
Erythropoietin stimulates RBC production in
kidney failure, leading to anemia.
deficiency of erythropoietin occurs in
is made and secreted by the kidney’s juxtaglomerular cells
Renin
decreased renal perfusion, decreased arterial BP, decreased ECF, decreased serum Na+ concentration, and increased urinary Na+ concentration.
Renin is released into the bloodstream in response to
a contributing factor in causing hypertension
Excessive renin production caused by impaired renal perfusion may be
(mainly PGE2 and PGI2) occurs primarily in the medulla.
kidney, PG synthesis
increasing renal blood flow and promoting Na+ excretion.
PGs have a vasodilating action, thus
the vasoconstrictive effect of substances such as angiotensin and norepinephrine.
PGs counteract
bowel preparations, such as magnesium citrate and Fleet enema, because the kidneys cannot excrete the magnesium
Patients with kidney failure should not receive some
contrast-induced kidney injury (CIN) and allergic reactions.
Iodine-based contrast media used in some diagnostic studies may cause
