ANATOMY - Lower Urinary Tract Flashcards
What are the three components of the lower urinary tract?
Paired ureters
Bladder
Urethra
What type of epithelium lines the ureters and the bladder?
Transitional epithelium/urothelium
How does urine travel along the ureters and into the bladder?
Urine is actively ‘milked’ along the ureters by peristaltic contractions of the smooth muscle of the ureter walls
Why do the ureters penetrate the urinary bladder at an angle?
To prevent reflux of urine as the bladder fills
What are the three main regions of the bladder?
Apex
Body
Neck
What anatomical landmark can be found at the apex of the bladder?
Scar of Urachus
What is the scar of urachus derived from?
The scar of Urachus is derived from a foetal structure which would shunt urine from the bladder into the allantois
What is the trigone of the bladder?
The trigone of the bladder is the small triangular region formed by the opening of the ureters and the beginning of the urethra
What suspends the neck of the bladder
The pelvic inlet
What are the two types of ligaments which suspend the body and apex of the bladder?
Paired lateral ligaments
Medial ligament
Why should you never cut through the lateral ligaments of the bladder?
Because the lateral ligaments of the bladder contain the umbilical arteries
What is the collective name for the smooth muscle layers of the bladder wall?
Detrusor muscle
What is the internal urethral sphincter?
The internal sphincter surrounds the opening of the bladder to the urethra and regulates the involuntary control of urine flow from the bladder into the urethra
What is the external urethral sphincter?
The external urethral sphincter is composed of the urethralis muscle located at the distal end of the urethra and regulates voluntary control of urine flow from the bladder into the urethra
What type of muscle is the urethralis muscle?
The urethralis muscle is a skeletal muscle
Which artery supplies the apex and part of the body of the bladder?
The cranial vesicle artery branched from the umbilical artery supplies the apex and part of the body of the bladder
Which artery supplies the neck and part of the body of the bladder in the female?
The caudal vesicle artery branched from the vaginal artery supplies the neck and part of the body of the bladder in the female
Which artery supplies the neck and part of the body of the bladder in the male?
The caudal vesicle artery branched from the prostatic artery supplies the neck and part of the body of the bladder in the male
Which artery supplies the urethra in the female?
The urethral artery branched from the vaginal artery supplies the urethra in the female
Which artery supplies the urethra in the male?
The urethral artery branched from the prostatic artery supplies the urethra in the male
Which nerve supplies parasympathetic innervation to the bladder?
Pelvic nerve supplies parasympathetic innervation to the bladder
Which nerves supply sympathetic innervation to the bladder?
Paired hypogastric nerves supply sympathetic innervation to the bladder
Which nerve supplies innervation to the voluntary control of micturition?
Pudendal nerve supples innervation to the voluntary control of micturition
What is the function of the parasympathetic pelvic nerve?
The pelvic nerve contracts the detrusor muscle to empty the bladder
What is the function of the sympathetic hypogastric nerves?
The sympathetic hypogastric nerves relax the detrusor muscle and contract the urethral smooth muscle for urinary retention
How does the pudendal nerve control micturition?
The pudendal nerve regulates the contraction of the urethralis muscle
What type of epithelium lines the urethra?
Stratified columnar followed by stratified cuboidal epithelium
