Urinary System Flashcards
4 kidney functions
Filter blood
Remove waste and toxins though urine
Control blood composition
Produce hormones and chemicals
How much fluid does the kidney filter /day
200L
How much urine is produced/day
1.5 L
What 3 components of blood are controlled by kidneys
Water
Electrolytes
pH
2 products secreted by kidneys
Renin– blood pressure
EPO– red blood cells
What vertebrae do the kidneys span?
T12- L3
Hilum
Medial margin of kidney– Entrance and exit for renal artery and vein
Which is more left, IVC or AA?
Abdominal aorta
What branches off of the IVC and AA
IVC– right and left renal veins
AA- Right and left renal arteries
Which renal artery is longer
Right
Which kidney is lower?
Right– pressed down by liver
3 structures next to right kidney
Liver
Ascending colon
Duodenum
5 structures next to left kidney
Pancreas Spleen Stomach Descending colon Jejunum
4 layers of kidney support
Parietal peritoneum
Renal fascia
Adipose capsule
Renal capsule
Renal capsule
Innermost layer, protects kidney
Adipose capsule
Protective fatty cushion below renal fascia
Renal fascia
Tough fibrous connective tissue anchors kidneys and adrenal glands– protects peritoneum from infection
2 things in the medulla of the kidney
Pyramids
Columns
Lobe
Renal pyramid and overlying cortex
- Produces urine
Flow of urine through renal sinus
Minor Calyx
Major calyx
Renal Pelvis
Ureter
6 big kidney blood supply vessels
Renal Segmental Lobar Interlobar Arcuate Interlobular
4 blood vessels in nephron
Afferent glomerular
Glomerulus
Efferent glomerular
Peritubular Capillaries
3 causes of kidney stones
Animal protein
High Na
Supplementary calcium
What size of stone will block ureter
Greater than 3mm
Prevalence of kidney stones
8-10%
– half the risk for women (estrogen as a protective factor)
Treatment for 70% of kidney stones
Extracorporeal Shock Wave Lithotripsy
Hydronephrosis
Ureter blockage leads to urine back flow into kidney
– water in kidney
3 causes of hydronephrosis
Kidney stones
Tumour
Pregnancy related compression
When do people need a kidney transplant
Less than 15% urinary function
Kidney Transplant
Third kidney inserted into pelvis. Renal artery of the kidney is connected the external iliac artery o f the recipient. The renal vein is attached to the external iliac vein. Ureter is attached to surface of the bladder
Nephron
Functional unit of kidney, absorbs ass much water as possible
Where does the urine produced by nephrons drain to
Thousands of collecting ducts collect urine and drain into minor calyx
Glomerulus
Cluster of blood vessels surrounded by the Bowman’s capsule
Bowmans capsule
Cup shaped membranous structure that extracts waste and excess ions
Proximal convoluted tubule
First wiggly part of nephron circulation before loop of henle
Distal convoluted tubule
Follows the ascending limb of loop of henle, ends in collecting duct
Arcuate artery
Runs between medulla and cortex of kidney
Cortical Nephrons
85% of nephrons– almost entirely in cortex
Peritubular Capillaries
Tiny branches off efferent arterioles for reabsorption, Surround PCT and DCT
Vasa recta
Peritubular capillaries covering the loop of henle
Juxtamedullary nephrons
Have a longer loop of henle that goes deeper into medulla. At the cortex-medulla interface, descending limb is more extensive
Renal tubule
Bowmans capsule, PCT, loop of henle, DCT
Renal corpuscle
Vascular connection between glomerulus and bowmans capsule
Renal tubule + corpuscle =
Nephron
Where do ureters start and how long are they
Begins at L2– 25-30cm long
Are ureters retroperitoneal?
Yes
Where do ureters enter the pelvis
Bifurcation of common iliac artery (into external and internal ), crosses the IVC and AA to enter into posterior bladder wall
3 sites where ureter makes a sharp turn
Ureter/renal pelvis– 90 degrees out of kidney
Cross iliac artery
90 degree turn to enter bladder
Bladder location
Posterior to pubic symphysis
Bladder capacity
700-800mL
– 400-600mL is stimulus for urination
Trigone
Smooth area without rugae in bladder, triangle between urethral and ureter openings
What would happen if there was no trigone
Stretching would close off the urethra
Where does the urethra exit the bladder
Neck
Internal urethral sphincter
At neck- controlled autonomically with detrusor muscles
External urethral sphincter
Floor of the pelvis– skeletal muscle
Potential space found in males and females
Retropubic: Between pubic symphysis and bladder. Filled with fat
Retrovesical Pouch
Found in males behind bladder. Can be compromised by disease
Location of uterus
Between bladder and rectum
Rectouterine pouch
Between rectum and uterus
Vesiocouterine pouch
Between uterus and bladder
Blood supply to bladder
Internal iliac artery branches into superior and inferior vesical arteries– superior to bladder
Urethral glands
Secrete a mucous lining to protect urethra from urine
Female urethra
4cm long straight tube from neck of bladder to vestibule
- Orifice and sphincters are all adjacent to each other
Male urethra
20 cm long, for urine and semen
Prostatic part of urethra
Most proximal– internal sphincter to prostate gland, includes prostate and ejaculatory ducts
Membranous part of urethra
Shortest segment passes through floor of pelvis. Contains external sphincter
Spongy part of urethra
Longest section goes through penis
Contains ejaculatory duct and orifice
Corpus Spongosium
Spongy tissue in penis
Bulbourethal Duct
Contributes to ejaculate
Micturition
Urination
Causes of UTI
Ecoli, sex
UTI sex ratio
5:1 for women– shorter urethras and are closer to internal organs
Age prevalences for UTI
Male– risk increases with age as prostate enlarges
Female– Highest risk at 20-30 when they are most sexually active
Urethritis
Dysuria
Frequency and urgency increase
Primarily effects women
Cystits
UTI ascends to bladder
Pyuria and bacteriuria make pee cloudy and smelly
Acute Pyelonephritis
UTI ascends to kidneys
Inflammation of calyces and pelvis
Erythropoietin
Stimulates RBC formation in bone marrow to increase oxygen carrying capacity
What 3 hypoxic conditions trigger EPO production
Reduced number of RBC– blood donation
Reduced availability of oxygen– altitude
Increased tissue demand for oxygen–exercise