Transport of urine from the kidney through the ureters and into the bladder. Micturition and micturition reflex. Volume and composition of the urine

Question 1

Transport of urine from the kidney through the ureters and into the bladder - 1

Answer 1

FILTRATION

Question 2

Transport of urine from the kidney through the ureters and into the bladder - 2

Answer 2

REABSORPTION
- PCT
- DESCENDING LIMB
- THIN ASCENDING LIMB
- THICK ASCENDING LIMB
- DCT
- CD

Question 3

Transport of urine from the kidney through the ureters and into the bladder - 3

Answer 3

SECRETION

in PCT/DCT

Question 4

URETER

Answer 4

smooth muscular tube

transports urine from kidney to bladder

• using peristalsis waves
• gravity
• hydrostatic pressure

Question 5

BLADDER

Answer 5

hollow organ
- trigone
- detrusor muscles - stretch
storage of urine

Question 6

URETHRA

Answer 6

releases urine (mic-urition)

• internal urethral sphincter = involuntary
• external urethral sphincter = voluntary

Question 7

micturition reflex - definition

Answer 7

• automatic response
• controlled by frontal lobe

when urinary bladder is filled with urine and needs to be expelled

Question 8

micturition reflex - mechanism

Answer 8

activation of stretch receptors

afferent pathway sends signals to to s2-s4 region

activation of efferent pathway sends signals to:
- detrusor muscle to contract
- internal urethral sphincter relax

Question 9

Volume of the urine

Answer 9

normal = 1.5L
polyuria = 3L
oliguria = less than 400ml
anuria = less than 100ml

Question 10

composition of urine

Answer 10

• water
• electrolytes (ions)
• urea/ uric acid/ creatinine

organic molecules
inorganic molecules