Urinary System Flashcards
Which structures compose the urinary system ?
- kidneys
- urinary tract : paired ureters, urinary bladder and urethra
Give 5 features of the kidneys
- paired and bean shaped
- retroperitoneal
- superior portion protected by 11th and 12th ribs (floating ribs)
- left and right height differences
- capped by adrenal gland for endocrine functions
What glands caps the kidneys ?
Adrenal glands
Which ribs protect the kidneys ?
11th and 12the ribs (floating ribs)
What are the left and right differences in kidney’s positioning in the body ?
- left kidney extends from T12 to L3
- right kidney is lower due to the liver
What are the 3 external layers of connective tissues protecting the kidneys ?
- renal fascia
- adipose capsule
- renal capsule
What is the role of renal fascia ?
It’s one of the 3 external layers of protective tissues of the kidneys.
It anchors each kidney to the peritoneum.
It anchors each kidney to the fascia covering the muscles of the posterior abdominal wall.
What is the role of the adipose capsule ?
It is one of the 3 external layers protecting the kidneys.
It protects the kidneys from shocks.
What is the role of the renal capsule ?
It is one of the 3 external layers protecting the kidney.
It covers the exterior of each kidney to protect them from infection and physical trauma.
What enters and exits through the hilium of the kidney ?
- renal artery
- renal vein
- renal nerves
- ureter
What are the 3 distinct regions of the kidney ?
- the inner renal pelvis
- the middle renal medulla
- the outermost renal cortex
Which structures compose the renal medulla ?
- renal pyramid
- renal column
What is the role of renal cortex and renal medulla together ?
Urine-forming portion of the kidney
What is the main role of renal pelvis ?
Drain the urine created by renal cortex and renal medulla
What is the functional unit of the kidney ?
The nephron
What are the functions of the nephrons ?
- filtering blood
- producing urine
What is the first urine draining structure ?
The papilla
After the processing of nephron what are the structure draining the urine ?
- papilla
- minor calyx
- major calyx (urine from 3 to 4 minor calyx)
- 3 to 4 major calyx drain the urine to the renal pelvis
- ureter
What is the cardiac output in kidneys ?
25% of all the cardiac output = 1200 mL per minute
Describe the arterial blood supply of the kidneys
- from right and left renal arteries (branch from abdominal aorta)
1) renal aorta
2) segmental artery
3) interlobar artery
4) arcuate artery
5) interlobar cortical radiate artery
6) afferent arteriole
7) glomerulus
8) efferent arteriole
9) peritubular capillaries
Describe the veinal blood supply of the kidneys
It parallel the arterial path
1) interlobular vein
2) arcuate veine
3) interlobar vein
4) renal vein
Empties in inferior vena cava
In which blood structure empties the renal vein ?
Renal veins exists the kidney through the hilium and then empties into the inferior vena cava.
What are the anterior anatomical relations of the left kidney ?
- suprarenal gland
- spleen
- stomach
- pancreas
- left colic flexure
- jejunum
What are the posterior anatomical relations of the left kidney ?
- diaphragm
- 11th and 12th ribs
- psoas major
- quadratus lumborum
- transversus abdominis
- subcostal nerve
- illiohypogastric nerve
- Illioinguinal nerve
What are the anterior anatomical relations of the right kidney ?
- suprarenal gland
- liver
- duodenum
- right colic flexure
What are the posterior anatomical relations of the right kidney ?
- diaphragm
- 12th rib
- psoas major
- quadratus lumborum
- transversus abdominis
- subcostal nerve
- illiohypogastric nerve
- illioinguinal nerve
What are the ureters ?
Urine leaves the kidneys through ureters that run posteriorly and connect to the urinary bladder.
They arise from the renal pelvis at roughly the level of L2, travel behind the peritoneum and empty in the bladder.
What is the role of urinary bladder ?
To store urine
What is the urethra ?
Tube connecting the bladder to the outside of the body to expell urine.
How does the one way flow of the ureter function ?
It’s a mechanism preventing urine from flowing backward through the ureter.
As urine is being collected in the bladder the pressure rises and compresses a tunnel in the bladder, pinching the ureter close and preventing back flow of urine.
What are the posterior anatomical relations of the right ureter ?
- psoas major
- genitofemoral nerve
What are the anterior anatomical relations of the right ureter ?
- duodenum
- branches of the superior mesenteric vessel
What are the inferior anatomical relations of the right ureter ?
Bladder
What are the anterior anatomical relations of the left ureter ?
- branches of the inferior mesenteric vessel
What are the posterior anatomical relations of the left ureter ?
- psoas major
- genitofemoral nerve
What are the inferior anatomical relations of the left ureter. ?
Bladder
Describe the urinary bladder
Hollow, distensible organ that sits on the floor of the pelvic cavity, suspended by a fold of parietal peritoneum.
How much urine can contain the bladder ?
700-800 ml for males, less in females due to the position of the uterus
What is the trigone ?
The floor of the urinary bladder contains a triangular area called trigone.
The two posterior corners of the trigone are formed by the two ureteral orifices.
Apex of the trigone is formed by is formed by the internal urethral orifice.
What is the role of the ureteral orifices ?
They act as valves to prevent the back flow of urine during elimination.
They form the two posterior corners of the trigone.
What are the anterior anatomical relations of the male urinary bladder ?
- rectum
- prostate
What are the anterior anatomical relations of the female urinary bladder ?
- vagina
What are the superior anatomical relations of the female urinary bladder ?
- uterus
What is the function of the urethra ?
Drain urine from the urinary bladder to the outside of the body.
What are the sphincters of urethra, what is their role ?
The urethra begins at the internal urethral orifice in the urinary bladder where it is surrounded by the internal urethal sphincter. This sphincter remains closed unless urine is being eliminated.
The external urethal sphincter is formed by the levatore ani muscle and the muscular floor of the pelvic cavity. It is composed by skeletal muscles and is under voluntary control.
Describe the female urethra
- opens at the urethral external orifice between the vagina and the clitoris
- it serves exclusively as a passage for urine
Describe the male urethra
Consists of 3 regions : - prostatic urethra - membranous urethra - spongy urethra It transports both urine and semen
