week 9 - urinary system Flashcards
female reproductive organs
vagina
uterus
uterine tubes
ovaries
sit in lesser pelvis
male reproductive organs
testes
epididymides
ductus deferentes
seminal vesicles
ejaculatory ducts
prostate
bulbourethral glands
urinary system organs
kidneys
ureters
muscular urinary bladder
urethra
kidneys function
excrete most of the waste products of metabolism
filter the blood, removing waste products and producing urine
controlling water volume and ion concentrations and in maintaining the acid/base balance of the blood
structure of kidneys
outer layer - cortex
inner layer - medulla
nephrons
pyramids of cortex drain urine into minor calyces which drain into major calyces which drain into renal pelvis
where structures enter or exit kidney - hilum
blood supply of kidney
renal arteries are two large branches of the abdominal aorta that arise just below the level of L1
divide into afferent arterioles which feed into glomeruli
efferent arterioles run from glomeruli and wrap round nephron
vasa recta - arterioles around loop of henle
adrenal glands
location, hormones
superior aspect of each kidney
hormones secreted from adrenal cortex - cortisol, aldosterone, sex hormones
hormones secreted from adrenal medula - adrenaline, noradrenaline
kidney stones aka renal calculi
crystal aggregations that form in collecting ducts of kidneys
caused by dehydration, diet
ureters
muscular tubes that empty urine from their respective kidney to urinary bladder
walls are 3 layers of smooth muscle fibres that spiral around tube and aid peristaltic contractions that force urine into the bladder
regions where ureters narrow
junction between ureters and renal pelvis
where ureters cross the brim of the pelvic bone
entrance of the ureters into the bladder
microanatomy of bladder wall
3 layers of smooth muscle - forms the detrusor muscle
internal and external layers are in similar longitudinal directional alignment
middle layer is aligned in circular direction
microanatomy of bladder epithelium
cells can stretch, shift over one another and flatten
full bladder is 2-3 cells thick
empty bladder 5-6 cells thick
position of bladder
adults empty - anteriorly in lesser pelvis
adults full - extends superiorly in extraperitoneal fat of the anterior body wall
infants <6 - bladder sits in abdomen even when empty
inside of bladder
posterior wall between ureteric orifices is the trigone (smooth triangular area)
rugae (ridges) - line majority of empty bladder + flatten out as bladder fills
sphincters of the bladder
junction between bladder and urethra is smooth muscle sphincter
controlled by autonomic innervation
internal urethral sphincter is only in males - prevents ejaculatory reflux of semen into bladder
