Elimination

Question 1

What is micturition?

Answer 1

The release of using from the urinary bladder so it can be eliminated

Question 2

What is the internal urethral sphincter ?

Answer 2

Smooth muscle which holds the bladder closed autonomically

Question 3

What is the external urethral sphincter?

Answer 3

Skeletal muscle which holds the bladder closes voluntarily

Question 4

How is the need to micturate stimulated?

Answer 4

As the bladder fills stretch receptors are stimulated until a conscious awareness informal is we need to micturate

Question 5

What muscle is the bladder formed of

Answer 5

The detrusor muscle which is layers of smooth muscle

Question 6

What does the bladder contains (nerves)?

Answer 6

Sensory nerve endings that communicate via the parasympathetic nervous system which responds to stretching

Question 7

What is the neck of the bladder where high numbers of nerve endings reside called?

Answer 7

Trigone

Question 8

How does the bladder stay closed?

Answer 8

Muscles at the base of the bladder stay closed to prevent leakage but it overridden when urine needs to be passed
Made up of smooth and striated muscle known as the internal and external sphincters

Question 9

What is the muscle which supports the bladder and urethra and contributes to continence called?

Answer 9

Pelvic floor muscle

Question 10

What are the nervous control centres involved in micturition?

Answer 10

Spinal micturition centre
Pontine micturition centre
Cerebral cortex
The hypothalamus

Question 11

How does the spinal micturition centre work?

Answer 11

Acts as a relay centre that organised incoming sensory information from the bladder

Question 12

How does the pontine micturition centre work?

Answer 12

Inhibits descending signals to the smc during filling and releases descending signals to smc to facilitate voiding of the bladder

Question 13

What role does the cerebral cortex play in micturition?

Answer 13

Allows voluntary inhibition of micturition reflex

Question 14

What role does the hypothalamus play in micturition?

Answer 14

Hormonal control of micturition

Question 15

How is urine emptied from the bladder?

Answer 15

Urine is emptied as the external urinary sphincter is voluntarily relaxed
The increased pressure and relaxation occurs as well as synchronised contractions of the bladder results in complete emptying

Question 16

What happens in the storage phase in the bladder?

Answer 16

Contractions of both sphincters

Inhibits of detrusor muscle

Question 17

What happens in the emptying phase in the bladder?

Answer 17

Relaxation of the sphincters

Contractions of the detrusor muscle

Question 18

What muscle makes up the pelvic floor?

Answer 18

Skeletal muscle

Question 19

How does the elimination of faeces work?

Answer 19

Colon exhibits slow waves of peristalsis which gently moves faces along
When in the rectum and sense of fullness and need to defaecate is produced

Question 20

What is rectal distension?

Answer 20

Relaxation of the internal anal sphincter which allows contents of the rectum to descend upper part of the anus
The walls contain sensory sensory nerves which distinguish the faecal consistency
Contractions resume and contents ascend back up into the rectum
External anal sphincter then allow us to control when to evacuate bowels