Lecture 33: THE URETERS, BLADDER AND URETHRA

Question 1

How are transitional epithelium cells?

Answer 1

Stratified, rounded

Question 2

What happens to transitional epithelium cells when stretched?

Answer 2

They flatten

Question 3

What is the purpose of transitional epithelium?

Answer 3

For protection from urine (waste product) returning to the underlying tissues

Question 4

Where do the ureters arise from?

Answer 4

The renal pelvis at each hilum

Question 5

What are the ureters?

Answer 5

Slender tubes that carry urine from kidneys to bladder

Question 6

Where do the ureters travel?

Answer 6

Descend retroperitoneally through the abdomen vertically from hila (has some curves)

Question 7

What moves urine to the bladder?

Answer 7

Peristaltic waves and gravity

Question 8

What are the layers of the ureter (inner to outer)?

Answer 8

Transitional epithelium, muscularis, adventiita

Question 9

How is the muscularis of the ureter?

Answer 9

Inner longitudinal and outer circular

Question 10

What is the adventitia?

Answer 10

Outer covering of FCT

Question 11

What is on the inner surface of the ureter?

Answer 11

Folded protective waxy protein plaques

Question 12

How do the ureters enter the bladder?

Answer 12

They run obliquely through the wall at its postolateral corners

Question 13

What does the ureter act as?

Answer 13

A sphincter/valve which is compressed by increases bladder pressure to prevent backflow

Question 14

What is the urinary bladder?

Answer 14

A collapsible muscular sac

Question 15

What does the urinary bladder do?

Answer 15

Stores and expels urine

Question 16

What does the urinary bladder do when empty?

Answer 16

Collapses along folds (rugae)

Question 17

What does the urinary bladder do when full?

Answer 17

Expands without great increase in pressure

Question 18

What is the volume of the urinary bladder?

Answer 18

Approximately 500ml

Question 19

What are rugae?

Answer 19

Folds that allow the bladder to expand

Question 20

What is the trigone?

Answer 20

Triangular region between 2 openings of entry of ureters and 1 opening for urethra

Question 21

What is the shape of an empty bladder?

Answer 21

Pyramidal

Question 22

Where is the bladder found when empty?

Answer 22

Lies within the pelvis

Question 23

What happens to the shape of the bladder as it fills?

Answer 23

It becomes more spherical

Question 24

Where is the bladder found when filling?

Answer 24

It expands superiorly into the abdominal cavity

Question 25

What can be done to the bladder when full?

Answer 25

It can be palpitated above the pubic symphysis

Question 26

Where is the male bladder found?

Answer 26

Anterior to the rectum and superior to the prostate gland

Question 27

What wraps around the male urethra?

Answer 27

The prostate gland

Question 28

Where is the female bladder found?

Answer 28

Anterior to vagina and uterus

Question 29

What is the urinary bladder wall folded into?

Answer 29

Rugae for expansion

Question 30

What is the mucosa of the urinary bladder?

Answer 30

Transitional epithelium

Question 31

What is the muscle of the urinary bladder?

Answer 31

Thick layer of smooth muscle called detrusor

Question 32

What fibres are in the detrusor?

Answer 32

Longitudinal, circular and oblique

Question 33

What does detrusor do?

Answer 33

Contractions expel urine from the bladder into the urethra during urination

Question 34

What is the urethra?

Answer 34

A thin walled muscular tube

Question 35

What does the urethra do?

Answer 35

Drains urine from the bladder out of the body

Question 36

How does the epithelium change in the urethra?

Answer 36

Transitional near the bladder, then columnar and stratified squamous near external opening

Question 37

Why is the epithelium transitional near the bladder in the urethra?

Answer 37

Because it needs to be able to stretch as urine enters

Question 38

Why is there columnar epithelium in the urethra?

Answer 38

Mucous to protect epithelium from urine (has mucus glands)

Question 39

What is the external opening of the urethra called?

Answer 39

External meatus/orifice

Question 40

Why is the epithelium stratified squamous at the external opening of the urethra?

Answer 40

Protection from abrasion

Question 41

What is the length of the female urethra?

Answer 41

Approximately 5cm

Question 42

Is the female urethra part of the reproductive system?

Answer 42

No, it is separate

Question 43

What is the length of the male urethra?

Answer 43

Approximately 25cm

Question 44

Is the male urethra part of the reproductive system?

Answer 44

Yes

Question 45

What is the initial section of the male urethra surrounded by?

Answer 45

Prostate gland which produces seminal fluid

Question 46

What are the sections of the male urethra?

Answer 46

Prostatic, membranous and spongy/penile

Question 47

Where is the internal urethral/urinary sphincter?

Answer 47

Junction of bladder and urethra

Question 48

What is the muscle of the internal urethral/urinary sphincter?

Answer 48

Detrusor muscle (smooth muscle under involuntary control)

Question 49

Where is the external urethral/urinary sphincter?

Answer 49

Where the urethra passes through the urogenital diaphragm

Question 50

What is the muscle of the external urethral/urinary sphincter?

Answer 50

Skeletal muscle under voluntary control

Question 51

What happens when the bladder fills?

Answer 51

It expands and causes an action potential from stretch receptors to be sent to the brain

Question 52

What happens as urgency to urinate occurs?

Answer 52

Increasing signal to the brain

Question 53

What sphincter relaxes first?

Answer 53

Internal sphincter and then conscious relaxation of the external sphincter