URINARY SYSTEM Flashcards
Filters nitrogenous wastes from the blood and helps regulate water, electrolyte, and acid-base balances
Urinary system
Location of the kidney
lower back, T12-L3 vertebra
Hormone released by the kidneys that stimulates red blood cell
erythropoietin
Kidney cells convert ___ produced in the skin to its active form
Vitamin D
Location of the kidneys
lower back, T12-L3 vertebra
Size of kidneys
12cm long, 6cm, wide, 3 cm thick
medial indentation of the kidneys
Renal hilum
transparent; encloses the kidneys and gives it a glistening appearance
fibrous capsule
fatty mass; surrounds each kidney and cushions it against blows
Perineal fat capsule
most superficial layer; made of dense fibrous connective tissue; anchors the kidney and adrenal gland to surrounding structures
renal fascia
outer region of the kidney and light in color
renal cortex
darker reddish brown area deep to the cortex; contains the renal/Medullary pyramids
renal medulla
triangular regions with striped appearance
Renal/Medullary pyramids
faces toward the cortex
base
points toward the inner region of the kidney
apex
extension of cortex like tissue that separates the pyramids
Renal columns
lateral to the hilum; flat, tunnel-shaped tube; continuous with the ureter leaving the hilum
renal pelvis
extensions of the pelvis; form cup-shaped drains that enclose the tips of the pyramids
calyces
Collect urine, which continuously drains from the tips of the pyramids into the renal pelvis
calyces
artery supplying each kidney
Segmental arteries - divisions of the renal artery as it approaches the hilum
renal artery
branches of the segmental arteries that travel through the renal columns to reach the cortex
interlobar arteries
branches from the interlobar arteries in the cortex-medulla junction
arcuate arteries
branch off the arcuate arteries to supply the renal cortex
Cortical radiate arteries
True or false: Venous blood draining from the kidney’s pathways is just reverse of the arterial supply
True
are the structural and functional units of the kidneys and are responsible for forming urine
Nephrons
collects fluid from several nephrons and conveys it to the renal pelvis
Collecting ducts
contains the glomerulus and glomerular capsule
renal corpuscle
a knot of capillaries
glomerulus
a cup-shaped hollow structure that completely surrounds the glomerulus like a well-worn baseball glove encloses a ball
Glomerular/Bowman’s capsule
octopus-like cells that make up the inner or visceral layer of the capsule
Podocytes
long branching extensions of podocytes that intertwine with one another and cling to the glomerulus
foot processes
openings between the processes that allow the podocytes o form a porous, or “leaky,” membrane around the glomerulus ideal for filtration
filtration slits
Extends from the glomerular capsule, it coils and twists before forming a hairpin loop and then again becomes coiled and twisted before entering a collecting duct
renal tubule
different regions of the renal tubule
proximal convoluted tube, nephron loop, distal convoluted tube
feeds the glomerulus
afferent arteriole
receives the blood as it leaves the glomerulus
efferent arteriole
arises from the efferent arteriole that drains the glomerulus
Peritubular capillaries
3 processes of urine formation
glomerular filtration, tubular reabsorption, and tubular secretion
Nonselective, passive process in which fluid passes from the blood into the glomerular capsule part of the renal tubule
Glomerular Filtration
what you call the fluid once it reaches the capsule
filtrate
When systemic blood pressure is ___, filtrate will be formed
normal
If arterial blood pressure ___, glomerular pressure becomes inadequate to force substances out of the blood into the tubules, and filtrate formation stops
drops too low
The tubule cells take the needed substances and return it to the blood
Tubular reabsorption
where does tubular reabsorption occur?
Proximal convoluted tubule
Essentially tubular reabsorption in reverse
Tubular secretion
Found in high concentrations in urine excreted from the body
Nitrogenous Wastes
formed by the liver as an end product of protein breakdown when amino acids are used to produce energy
Urea
released when nucleic acids are metabolized
Uric acid
associated with creatine metabolism in muscle tissue
Creatinine
Within 24 hours, the kidneys filter some ___ liters of blood plasma through their glomeruli into the tubules
150-180
In the same 24 hours, only about ___ liters of urine are produced
1-1.8
True or false: By the time the filtrate reaches the collecting ducts, the filtrate still contains all the nutrients
False: all of its water, nutrients, and ions. What remains is urine.
yellow pigment that results from the body’s destruction of hemoglobin
Urochrome
True or false: The more solutes are in the urine, the deeper yellow its color
true
True or false: Vegetable can alter the odor of urine
True: Drugs, vegetables, and various diseases can alter the urine odor
Two slender tubes each 25 to 30 cm (10 to 12 inches) long and 6 mm (¼ inch) in diameter; connects the kidneys and bladder
Ureters
A smooth, collapsible, muscular sac that stores urine temporarily
urinary bladder
3 openings of the urinary bladder
2 urethral orifices and the urethra
The smooth triangular region of the bladder base outlined by these three openings
Trigone
3 layers of smooth muscle that comprises the bladder wall
Detrusor muscle
mucosa of the bladder wall
Transitional epithelium
Size of the bladder when it is empty
5-7.5 cm
Size of a moderately full bladder
12.5 cm
Moderately full bladder holds how much volume?
500 ml
True or false: When the bladder is full, it is soft and shaped like an apple
False. The bladder would be firm and pear-shaped
Thin-walled tube that carries urine by peristalsis from the bladder to the outside of the body
Urethra
keeps the urethra closed when urine is not being passed
Internal urethral sphincter
formed by skeletal muscle as the urethra passes through the pelvic floor; voluntarily controlled
External urethral sphincter
3 regions of the male urethra
prostatic, membranous, and spongy
Size of a woman’s urethra
3-4 cm
Size of a man’s urthra
20 cm
The act of emptying the bladder
Micturition
Percentage of water in an adult woman
50%
Percentage of water in an adult man
60%
Percentage of water in babies
75%
Percentage of water in older people
45%
main locations in the body where water occupies
Fluid compartments
contained in living cells and makes up two/thirds of body fluid
Intracellular fluid
includes all body fluids outside the cells
Extracellular fluid
serves as the highway that links the external and internal environments because it deliver substances
Plasma
True or false: If the body is to remain properly hydrated, it cannot lose more water than it takes in
True
driving force for water intake
thirst mechanism
When thirsty, the mouth also becomes dry because the ___ obtain the water they require from the blood
salivary glands
helps regulate the amount of water in your body by controlling the amount of water your kidneys reabsorb as they filter out waste from your blood
Antidiuretic hormone
second hormone that helps to regulate blood composition and blood volume by acting on the kidney
aldosterone
are the electrolytes most responsible for osmotic water flow
sodium ions
What causes edema?
when the sodium ion levels are low, water leaves the blood and enters tissues
most important trigger for aldosterone release
Renin-angiotensin mechanism
initiates the series of reactions that produce angiotensin II.
Renin
Causes vasoconstriction.
Angiotensin II
above 7.45 pH of arterial blood
Alkalosis
below 7.45 pH of arterial blood
Acidosis
