Introduction, gross anatomy and histology Flashcards
What structures make up the urinary system?
o Kidneys
o Ureters
o Urinary bladder
o Urethra
What are the functions of the urinary system?
- Removes metabolic waste from blood by filtration and excretion
- Regulates blood pressure (by renin-angiotensin mechanism)
- Regulates plasma concentrations of electrolytes (sodium, potassium and chloride etc.)
- Help to stabilize the pH
- Conserves valuable nutrients
- Reabsorption of small molecules (amino acids, glucose and peptides)
- Kidney produces erythropoietin (a stimulant of RBC production by bone marrow)
Where are the kidneys found?
- The kidneys lie in a retroperitoneal position at the level of T12-L3.
- Right kidney is slightly lower than the left kidney due to the liver
At what vertebral levels are the kidneys found?
T12-L3
How many pyramids are in each kidney?
10-18
Define a renal lobe
Renal lobe - portion of a kidney consisting of a renal pyramid and the renal cortex above it
List the contents of the hilum of the kidney and their locations
Vein artery pelvis - from anterior to posterior
Describe the arterial supply of the kidneys
Renal artery (1/each side): branch of abdominal aorta.
o Segmental branches (x5)
o Interlobar
o Arcuate branches pass around the circumference
o Interlobular branches and ultimately supply each nephron
o Essentially non-anastomosing
Describe the venous drainage of the kidneys
Renal veins (1/each side): drains into the inferior vena cava
Describe the lymphatic drainage of the kidneys
Lateral aortic lymph nodes
Describe the nerve supply of the kidneys
Renal plexus:
- sympathetic: T10-L1
- Sensory afferent: T11-L2
Describe the arterial supply of the ureters
renal artery
ovarian/testicular artery
abdominal aorta
Describe the venous drainage of the ureters
renal veins
ovarian/testicular veins
What is the median umbilical ligament a remnant of?
embryonic urachus
Where are the two medial umbilical folds found?
Two medial umbilical folds – on the occluded umbilical artery of bladder
Where are the two lateral umbilical folds found?
Two lateral umbilical folds – on the inferior epigastric vessels
What is the peritoneal fold found between the uterus and rectum called?
Pouch of Douglas
What is the clinical relevance of the pouch of douglas?
Pouch of Douglas is a peritoneal fold between the uterus and the rectum, and is a common site for the spread of pathology such as ascites, tumour, endometriosis, pus, etc.
Describe the arterial supply of the bladder
Branches of the internal iliac arteries
Describe the venous drainage of the bladder
Tributaries of the internal iliac veins
Describe the lymphatic drainage of the bladder
– External iliac: suprapubic part
– Internal iliac: Infrapubic part
Which sphincters of the urethra are voluntary or involuntary?
Internal sphincter - involuntary
External sphincter - voluntary
What makes up a nephron?
Nephron = renal corpuscles + renal tubules
What makes up a renal corpuscle?
Renal corpuscles = glomerulus + bowman’s capsule
What makes up a uriniferous tubule?
Uriniferous tubule = nephron + collecting duct
What structure within the urinary system has a star shaped lumen?
Ureter
Describe the epithelium of the proximal convoluted tubule
Cuboidal epithelium with microvilli
Describe the epithelium of the distal convoluted tubule
Cuboidal epithelium
Describe the epithelium of the collecting tubule
Cuboidal epithelium
What part of the kidney has renal corpuscles
Cortex
Describe the epithelium of the Loop of Henle
Squamous epithelium
Describe the muscle layers surrounding the ureters
Inner longitudinal smooth muscle
Outer circular smooth muscle
Describe the epithelium of the bladder
Transitional epithelium
Describe the muscle layers surrounding the bladder
Inner longitudinal smooth muscle
Middle circular smooth muscle
Outer longitudinal smooth muscle
Describe the clinical relevance of the urinary system
- Urinary tract infection (UTI) – very common in females due to short length of ureter/proximity to the anus
- Glomerulonephritis
- Kidney stone/renal calculi
- Kidney failure and dialysis
- Urinary incontinence: common after childbirth, in old age or in females
What is an important marker of chronic kidney disease?
- High protein (albumin) levels in the urine
* Kidney function is most commonly assessed by estimating glomerular filtration rate (GFR) by use of serum creatinine.
How is kidney function estimated?
Kidney function is most commonly assessed by estimating glomerular filtration rate (GFR) by use of serum creatinine.
List some common embryological abnormalities
- Aberrant renal arteries
- Pelvic kidney
- Unilateral double kidney
- Double ureter
- Horseshoe kidney
Which nerve constricts detrusor muscle during micturition (urination)?
A) Sympathetic nerve
B) Parasympathetic nerve
C) Sensory nerve
D) Somatic/pudendal nerve
B) Parasympathetic nerve
Which nerve constricts internal urethral sphincter during ejaculation?
A) Sympathetic nerve
B) Parasympathetic nerve
C) Visceral sensory nerve
D) Somatic/pudendal nerve
A) Sympathetic nerve
Which is the narrowest part of the urethra in male?
A) Pre-prostatic
B) Prostatic
C) Membranous
D) Spongy
C) Membranous
The Transpyloric plane passes through which vertebral level?
A) T11
B) T12
C) L1
D) L2
C) L1
