URINARY SYSTEM Flashcards
flow of urine in the urinary system
kidneys, ureters, urinary bladder, urethra
the kidney disposes wastes products in the urine such as
nitrogenous wastes
toxins
drugs
excess ions
it maintains maintain BP in the kidney
renin
it stimulates RBC production in kidney
eryhthropoietin
what happens to Vit D in the kidney
converted into its active form
location of kidneys
dorsal body wall at the parietal peritoneum
at what level are kidneys situated
T12 to L3 vertebrae
formation of kidney (which is lower an dhigher)
right kidney is slightly lower than the left
A medial indentation where several structures enter or exit the kidney
renal hilum
it sits atop each kidney
adrenal gland
3 protective layers enclosing the kidney
fibrous capsule
perirenal fat capsule
renal fascia
encloses each kidney
fibrous capsule
surrounds the kidney and cushions against blows
perirenal fat capsule
most superficial layer of the kidney and adrenal gland surrounding structures
renal fascia
3 regions of the kidney (longitudinal section)
renal cortex
renal medulla
renal pelvis
outer region that provides space for arterioles, venules, & glomerulus capillaries, which connect the nephrons
renal cortex
next to renal cortex
renal medulla
triangular regions of tissue in the medulla
renal/medullary pyramids
extensions of cortex like material that separate the pyramids
renal columns
medial region that is a flat, funnel-shaped tube
renal pelvis
cup shaped drains that encloses the renal pyramids
calyces
provides each kidney with arterial blood supply
renal artery
venous blood flow
A RSI ACA G EPCA IRI
structural functions of kidney
nephrons
kidney nephrons structure (2)
renal corpuscle
renal tubule
2 R. Corpuscle
glomerulus
glomerular or bowman’s capsule
a knot of capillaries made of podocytes
glomerulus
make up the inner (visceral) layer of the glomerular capsule
podocytes
is a cup-shaped structure that surrounds the
glomerulus
Glomerular (Bowman’s) capsule
Extends from glomerular capsule and ends when it empties into the
collecting duct
R. Tubule
3 subdivisions of R. Tubule
- Proximal convoluted tubule (PCT)
- Nephron loop (loop of Henle)
- Distal convoluted tubule (DCT)
Located entirely in the cortex
cortical nephrons
Found at the cortex-medulla junction
juxtamedullary nephrons
2 capillary beds associated with nephron
- Glomerulus
- peritubular capillary bed
specialized for filtration
glomerulus
in glomerulus, what forces fluid and solutes out of blood and into the glomerular capsule
HBP
Adapted for absorption instead of filtration
peritubular capillary bed
3 processes of urine formation
- Glomerular Filtration
- Tubular reabsorption
- tubular secretion
what kind of process occurs in the filtration in the glomerular
passive process
what are forced through glomerular capillary walls
water and solute
Filtrate will be formed as long as
systemic blood pressure is normal
what useful substances are reabsorbed from the renal tubule
water
glucose
amino acids
ions
T. reabsorption, passive or active process
most are active
most reabsorption occurs in the
proximal convoluted tubule
what does T. secretion release
hydrogen and potassium ions
creatinine
why is T. Secretion important
Getting rid of substances not already in the filtrate
Removing drugs and excess ions
Maintaining acid-base balance of blood
Nitrogenous wastes in the urine
urea
uric acid
creatinine
end product of protein breakdown
urea
results from nucleic acid metabolism
uric acid
associated with creatine metabolism in muscles
creatinine
contains everything that blood plasma does (except
proteins)
filtrate
it is what remains after the filtrate has lost most of its
water, nutrients, and necessary ions through reabsorption
urine
what pigment in the urine causes the yellowish color
urochrome and solutes
liver destroys hemoglobin
urochrome
solutes in urine
Sodium and potassium ions
○ Urea, uric acid, creatinine
○ Ammonia
○ Bicarbonate ions
what condition is caused by glucose
glycosuria
what condition is caused by proteins
proteinuria
what condition is caused by proteins
proteinuria
what condition is caused by pus (WBCs & bacteria)
pyuria
what condition is caused by RBCs
hematuria
what condition is caused by hemoglobin
hemoglobinuria
what condition is caused by bile pigment
bilirubinuria
non pathological cause of glycosuria
excessive intake of sugary foods
pathological cause of glycosuria
diabetes mellitus
non pathological cause of proteinuria
physical exertion & pregnancy
pathological cause of proteinuria
glomerulonephritis
hypertension
what causes pyuria
UTI
what causes hematuria
bleeding in UT due to trauma, kidney stones, infection
what causes hemoglobinuria
transfusion reaction,
hemolytic anemia
what causes bilirubinuria
transfusion reaction,
hemolytic anemia
Slender tubes 25–30 cm (10–12 inches) attaching the kidney to the urinary bladder
ureter
ureter continues to the
renal pelvis
aids gravity in urine transport
peristalsis
Smooth, collapsible, muscular sac situated posterior to the pubic
symphysis
urinary bladder
stores urine temporarily
urinary bladder
triangular region of the urinary bladder base based on three
openings
trigone
the trigone has
two openings from the ureters (ureteral orifices)
one opening to the urethra (internal urethral orifices)
in males, what surrounds the neck of urinary bladder
prostate
urinary bladder – Three layers of smooth muscle
detrusor muscle
made of transitional epithelium
mucosa
Thin-walled tube that carries urine from the urinary bladder to the outside of the body by peristalsis
urethra
function of urethra in
males -
females -
carries urine
carries urine and sperm
in urethra, the release of urine is controlled by two sphincters: which is voluntary and invo?
- internal urethral sphincter (invo)
- external urethral sphincter (vol)
loc of urethra in males and females
males - prostatic urethra, membranous urethra, spongy urethra
females - anterior to vaginal opening
emptying of the urinary bladder
micturition
transmit impulses to the sacral region of the spinal cord
stretch receptors
what causes contractions when impulses travel back to the bladder
pelvic splanchnic nerves
Blood composition depends on three factors
diet
cellular metabolism
urine output
four roles in maintaining blood composition
- Excreting nitrogen-containing wastes
- Maintaining water balance of the blood
- Maintaining electrolyte balance of the blood
- Ensuring proper blood pH
normal amount of water in young adult females
50%
normal amount of water in young adult males
60%
normal amount of water in babies
75%
normal amount of water in the elderly
45%
3 main compartments of water
- Intracellular Fluid (ICF)
- Extracellular Fluid (ECF)
- Plasma
● Fluid inside cells
● Accounts for two-thirds of body fluid
Intracellular Fluid
Fluids outside cells; includes blood plasma, interstitial fluid
(IF), lymph, and transcellular fluid
ECF
Links external and internal environments
plasma
is the driving force for water intake
thirst mechanism
sensitive cells in the hypothalamus that become more active in reaction to small changes in plasma solute concentration
Osmoreceptors
source of water output
lungs
perspiration
feces
urine
primarily responsible for reabsorption of water and
electrolytes by the kidneys
hormones
prevents excessive water loss in the urine and increases water reabsorption
Antidiuretic hormone (ADH)
are charged particles (ions) that conduct electrical current in an aqueous solution
electrolytes
ex of electrolytes
Sodium, potassium, and calcium ions
helps regulate blood composition and blood volume by acting on the kidney
aldosterone
Most important trigger for aldosterone release
Renin-angiotensin mechanism
what mediates Renin-angiotensin mechanism
juxtaglomerular (JG) apparatus
The renin-angiotensin system works due to a
drop in blood pressure and blood volume
Alkalosis
pH above 7.45
Acidosis
pH below 7.35
Physiological acidosis
pH between 7.0 and 7.35
play greatest role in maintaining acid-base balance
kidneys
Other acid-base controlling systems
blood buffers, respiration
acids are __; bases are __
proton donors; proton acceptors
Three major chemical buffer systems
- Bicarbonate buffer system
- Phosphate buffer system
- Protein buffer system
the bicarbonate buffer system is a mixture of
carbonic acid (H2CO3) and
sodium bicarbonate (NaHCO3)
it is a weak acid that does not dissociate much in neutral or acid solutions
carbonic acid
react with strong acids to change them to weak acids
bicarbonate ions
it dissociates in the presence of a strong base to form a weak base and water
Bicarbonate ions
in respiratory mechanisms, blood pH __ when CO2 retains, but is blood pH __ when CO2 is removed
decrease
increase
In renal mechanisms, Bicarbonate ions are excreted and Hydrogen ions are retained by kidney tubules
blood pH rises
in renal mechanisms, Bicarbonate ions are reabsorbed and Hydrogen ions are secreted
blood pH falls
when does kidney begin to develop
first few weeks of embryonic life
when does the kidney start to excrete urine
third month of fetal life
congenital abnormalities
polycystic kidney
hypospadias
cluster of cysts forms in the kidney
polycystic kidney
opening of the urethra is at the underside of the penis instead of at the tip
hypospadias
Common urinary system problems in children and young to
middle-aged adults include infections caused by
fecal microorganisms,
microorganisms causing sexually transmitted infections, and
Streptococcus
the only common problems before old age
UTI
a bacterium, accounts for 80 percent of UTIs
Escherichia coli (E. coli)
an uncommon but serious problem in which the kidneys are unable to concentrate urine
renal failure
what must be done in kidneys to maintain chemical homeostasis of blood
dialysis
With age, filtration rate __and tubule cells become less
efficient at concentrating urine
decreases
problems associated with aging
urgency
frequency
nocturia
incontinence
urinary retention
feeling that it is necessary to void
urgency
frequent voiding of small amounts of urine
Frequency
need to get up during the night to urinate
Nocturia
loss of control
Incontinence
inability to completely empty the bladder
Urinary retention
common in males prostate gland a type of Urinary retention
hypertrophy
