The Kidney (Urinary System Section) Flashcards
Kidney Anatomy
long/thick/wide? oz? located where? positioning?
About 4-5 in. long, 2-3 in. wide, 1 in. thick
4.5-5oz
Located btwn 12th thoracic & 3rd lumbar vertebrae
Right kidney slightly lower than left (bc of liver on the right)
Tissue Coverings of the Kidney
how many layers? what are they?
3 tissue layers:
- Renal Capsule
- Adipose capsule
- Renal Fascia
Renal Capsule
description? function?
(covering of kidney)
deepest- dense connective tissue
helps maintain shape & keep infections out
Adipose capsule
description? function?
middle layer- fatty
protects & holds kidneys in place
Renal Fascia
description? function?
outer layer- thin dense irreg. connective tissue
holds kidneys to abdominal wall
Nephrons
def? how many? consists of what 2 parts?
functional unit of kidney 1 million nephrons per kidney consists of 2 parts: -Renal Corpuscle -Renal Tubule
(Nephron part)
Renal Corpuscle
contains (2)? function?
Glomerulus-capillary netowrk
Bowman’s Capsule-double walled epithelial cells (collects from diffusion btwn)
Function: Blood plasma filteration
(Nephron part)
Renal Tubule
what are the 3 sections?
3 sections:
- proximal convoluted tubule
- loop of henle (nephron loop)
- distal convoluted tubule
(Nephron part)
Renal Tubule
-proximal convoluted tubule (description? location? funct?)
highly coiled portion
located in cortex
reabsorption & secretion take place
(Nephron part)
Renal Tubule
-loop of Henle (nephron loop) (location? composed of (2)?)
located in cortex and renal medulla
ascending limb of Henle
descending limb of Henle
(Nephron part)
Renal Tubule
-distal convoluted tubule (location? description? funct.?)
located in cortex
highly coiled
empty into collecting duct
Why are there 3 sections of the Renal Tubule?
it allows for greatest surface area for exchange
Types of Nephrons
Cortical Nephrons
Juxtamedullary Nephron
(Types of Nephrons) Cortical Nephrons (description & location?)
short nephron loops
renal cortex
(Types of Nephrons) Juxtamedullary Nephron (description & location?)
long nephron loops renal medulla (except Bowman in cortex)
Urine Formation
What are the 3 parts?
3 parts:
1) Glomerular Filtration
2) Tubular Respiration
3) Tubular Secretion
(Urine Formation)
2) Tubular Respiration
what 4 parts are involved?
- Proximal convoluted tubule (PTC)
- Loop of Henle
- Distal Convoluted Tubule (DCT)
- Collecting Duct
(Urine Formation)
3) Tubular Secretion
- Proximal convoluted tubule (PTC)
- Nephron Loop
- Collecting Duct
(Urine Formation)
2) Tubular Respiration
what does the Proximal convoluted tubule (PTC) reabsorb?
Na, Cl, H2O, glucose, amino acids
(Urine Formation)
2) Tubular Respiration
what does the Loop of Henle reabsorb?
Descending limb: H2O
Ascending limb: Na, Cl, Ca, Mg, K
(Urine Formation)
2) Tubular Respiration
what does the Distal Convoluted Tubule (DCT) reabsorb?
Na, K, Cl (same as collecting duct)
(Urine Formation)
2) Tubular Respiration
what does the collecting duct reabsorb?
Na, K, Cl (same as Distal Convoluted Tubule (DCT))
(Urine Formation)
3) Tubular Secretion
what does the Proximal convoluted tubule (PTC) secrete?
H+, ammonia, urea, & creatine
(Urine Formation)
3) Tubular Secretion
what does the nephron loop secrete?
urea
(Urine Formation)
3) Tubular Secretion
what does the collecting duct secrete?
H+, K+
(Urine Formation)
3) Tubular Secretion
is basically?
ions & by products of metabolic reactions
Order of tissue layers of the kidney from deep to superficial
body of kidney
renal capsule
adipose capsule
renal fascia
What is urea? how is the amount eliminated determined? percentage in urine?
product of amino acid metabolism in the liver
-amount eliminated determined by amount of protein in diet
50% excreted in urine
Uric acid
What is it? percentage excreted in urine?
product of nucleic acid bases (adenine & guanine) metabolism
10% excreted in urine
What is urine Composed of? (5)
1) 95% water
2) Urea
3) Uric acid
4) Electrolytes
5) Ammonia
how much urine is produced per day?
1-2 Liters/day
color of urine?
yellow to amber color
transparent
pH of urine?
4.6-8, avg. 6.0
Water balance
described as?
water in = water out
Water Balance
Take in water by…?
Take in water:
- 1) drinking (most)
- 2) eating foods w/ water
- 3) chemical reactions (cell respiration)
When is your urine more acidic, why?
more acidic when you wake up & darker
bc not eating or drinking anything
ammonia is a result of what in your urine?
too much high protein
urine dark yellow indicates..?
a lot of protein
Water Balance
Lose water by…?
- 1) Excretion by kidneys
- 2) Evaporation from skin
- 3) Exhalation
- 4) Through feces
Normal daily water loss/ gain
2500 mL
Diuretics
def? causes? ex?
(drugs or chemicals)
substance that slows reabsorption of water by kidneys
causes elevated urine flow
ex) caffeine
Urine Elimination - Ureters
measure? what occurs?
25 cm long
peristalsis waves carry urine to bladder
Urine Elimination- Urinary Bladder
function/ how much? description? contains (3)?
Stores urine- 700-800mL Empty- folded, Full-smooth Detrusor muscle Trigone Internal urethral sphincter
(Urinary Bladder)
Detrusor muscle
general description?
3 layers of smooth muscle
(Urinary Bladder)
Trigone
def? description?
triangular area on floor of bladder
-3 openings - open into urethra
(Urinary Bladder)
Internal urethral sphincter
function?
holds in urine (sphincters work opposite from the system)
Urine Elimination- Urethra
tube conveying urine to outside of body
Urine Elimination occurs from what down? location
kidneys down, behind small and large intestine
Micturition (urination)
Process (4)?
1) Full bladder stimulates parasympathetic motor nerves to stimulate detrusor muscle
2) External urethral sphincter relaxes and detrusor muscle contracts
3) Urine flows out of body
4) External urethral sphincter contracts and detrusor muscles relax
how are sphincters in the urinary system different from the digestive system?
Sphincters work opposite of bladder muscles
Renal cortex`
description? purpose?
light red outer region
receives most of blood supply
Renal medulla
description? composed of and contains?
dark brown inner region
composed of renal pyramids
contains tubules to collect urine
Renal pelvis
description? composed of (2)? purpose?
funnel shaped cavity
composed of: major and minor calyces
-collects urine and drains into ureters
Renal Veins
(left and right) drain blood from the kidneys
kidneys
regulate what? secrete what? excrete what?
(left and right)
regulate blood volume, blood pressure, blood ionic composition, blood pH, and blood glucose
secrete 2 hormones (Calcitriol and erythropoietin)
excrete wastes
Renal Blood Supply
amount? percentage? flows through..?
1200 mL/min through kidney
-20-25% cardiac output
(blood flows) through renal arteries and veins
path of blood flow
renal artery (large -> small -> back) segmental arteries cortical radiate arteries arcuate arteries cortical radiate arteries afferent arterioles glomerulus efferent arterioles peritubular capillaries cortical radiate veins arcuate veins interlobular veins renal vein
