Urinary continence

Question 1

What are the main functions of the bladder? (2)

Answer 1

• Collects urine

- Stores it under LOW PRESSURE conditions

Question 2

What are the bladder walls made of?

Answer 2

Smooth muscle - detrusor muscles

Question 3

What muscles are contracting when bladder is filling?

Answer 3

Internal urethral sphincter

External urethral sphincter

Question 4

What muscles are relaxed when bladder is filling?

Answer 4

Detrusor muscles

Question 5

What muscles are contracting during micturition?

Answer 5

Detrusor muscles

Question 6

What muscles are relaxing during micturition?

Answer 6

Internal urethral sphincter

External urethral sphincter

Question 7

What type of innervation causes detrusor muscles to contract?

Answer 7

Parasympathetic innervation

Question 8

What is the bladder stretch reflex?

Answer 8

Primitive spinal reflex - not functional post childhood

Question 9

What does parasympathetic innervation do to the bladder? (3)

Answer 9

Allows micturition

• Contraction of detrusor muscles
• Relaxation of internal & external urethral sphincters

Question 10

What are the nerves involved in micturition? (3)

Answer 10

Pelvic splanchnic nerve (T12-L2) - contracts detrusor
Hypogastric nerve (S2-S4) - contracts IUS
Pudendal nerve (S2-S4) - contracts EUS