Structure and anatomy of the urinary system Flashcards
what is the function of the urinary system?
through filtration and selective reabsorption, precise control of concentration of key substances in the ECF
what are examples of substances requiring control in the urinary system?
ions, small organic molecules and water
what does this process maintain?
a stable internal environment
what must the kidney do? (functions)
- control volume
- control osmolarity
- help to control pH
- excrete some waste products
how does the kidney control these functions?
filtering a large amount of ECF, each litre of ECF is filtered over 10 times a day - nearly all is recovered (>99%)
where are the kidneys located?
the kidneys are retroperitoneal organs that sit either side of the spine in the abdominal cavity
roughly which level are the kidneys located?
T12-L3
which kidney sits lower? why?
right kidney sits lower, because of the position of the liver
when do kidneys have mobility and of how much?
3cm when we breathe due to their proximity to the diaphragm
what are the tops of the kidneys protected by?
11th and 12th ribs
where does the bladder sit in adults?
right behind the pubic bone
where does the bladder sit in child?
above the pubic bone
what happens to the bladder as it fills up with urine?
distends upwards
where is the prostate situated?
directly below the bladder
what passes through the prostate?
the urethra
what can happen if the prostate undergoes hypertrophy?
prevent urination
where do the ureters arise from?
the renal pelvis on the medial aspect of each kidney
where do the ureters descend?
towards the bladder on the front of the psoas major muscle (moving laterally to medially)
where do the ureters cross the pelvis brim?
near the bifurcation of the iliac arteries (cross anteriorly over the common iliac)
what happens after the ureters cross the iliac arteries?
under the uterine artery / vas deferens and down the pelvic sidewall
where do the ureters insert into?
posterior surface of the bladder
what are the 3 points that kidney stones are likely to occur?
- the junction of the renal pelvis and the ureter
- the point at which ureters cross the brim of the pelvis (iliac bifurcation)
- where the ureters pass into the wall of the urinary bladder
what surrounds the kidney?
fibrous capsule
what is the renal cortex?
outer portion of the kidney
what does the renal cortex form?
a continuous smooth outer zone with a number of projections
what are the projections of the kidney called?
cortical columns
where do the cortical columns extend down between?
the pyramids
what does the renal cortex contain?
glomerulus and Bowman’s capsule
where does ultrafiltration take place?
in the cortex
what does the renal cortex also contain?
renal tubules, except for parts of the loop of Henle
where does the loop of Henle descend into?
the medulla
