L33: Urinary System Flashcards
role of kidneys
filter waste products from bloodstream
- convert filtrate to urine
function of ureters?
transport urine from kidney to bladder via peristalsis
function of urinary bladder?
storage of urine
function of urethra?
transports urine from bladder to outside body
more functions of the kidneys?
- Regulation of blood volume & pressure
- Regulation of erythrocyte production
via erythropoietin - Regulation of the blood’s inorganic ion
balance –sodium, potassium and
phosphate ions - Acid-base balance through changes in
the rates of hydrogen ion and
ammonium secretion
What are kidneys attached to?
- NOT ligaments
- held in position by their adipose capsule (soft tissue cushion)
if adipose tissue melts, what occurs?
“mobile kidney”
what is renal fascia?
- dense irregular tissue
- anchors kidney to surrounding tissues
what is adipose capsule and adipose tissue?
capsule: fat with adipose tissue
tissue: cushioning and insulation
what is the renal capsule?
- dense connective tissue
- maintains kidney shape
- protects from pathogens
What does the renal sinus contain?
- minor/major calices
- renal pelvis
- renal fat
- blood vessels
what is the access to the renal sinus?
renal hilum
What is glomerulus?
- arterial capillary system (unique in body)
- important for blood filtration
What is renal corpuscle?
- composed of a capillary network (glomerulus)
- produces a filtrate of blood
what surrounds glomerulus?
- the glomerular capsule (bowman capsule)
function of proximal convoluted tubule?
- reabsorbs ions, nutrients, plasma proteins, vitamins and water
- filtrate is now called tubular fluid
function of distal convoluted tubule?
- secretes ions into the tubular fluid and reabsorbs water
function of bowman’s capsule?
filtration
function of loop of henle?
reabsorption of ions and water
function of collecting duct?
for urine
structure of ureters?
- 25-30cm long fibromuscular tubes
- extend from renal pelvis and exit the hilum of kidney
- paired
- retroperitoneal
how do ureters transport urine?
peristaltic action of smooth muscle
what are the 3 layers of ureters?
- mucosa (innermost)
- muscularis
- adventina (outermost)
function of mucosa in ureters?
- transitional epithelium stretchy to passage of urine
- bundles of primarily smooth muscle fibres surround mucosa/ help propel urine outside body
function/structure of muscularis in ureters?
- 2 smooth muscle layers (inner longitudinal & outer circular)
- peristaltic waves propel urine
structure/function of adventina?
- areolar connective tissue
- anchors ureter to posterior abdominal
structure/function of urinary bladder?
- expandable muscle reservoir for urine
- retroperitoneal
- shaped like upside-down pyramid when empty
- when full; distended superiorly and oval shaped
how does the urinary bladder receive blood
branches of the internal iliac arteries
location and function of the parasympathetic axons (pelvic splanchnic nerves)
- come from micturition reflex center located in spinal cord S2-S4
- stimulate urination
location/ function of the sympathetic axons
- T11-L2 spinal cord
- inhibit micturition
what is micturition?
urination
True or False:
The urethra is sexually dimorphic
true
what is the prostatic urethra in the male urethra?
- 3cm long
- extends through prostate gland where multiple small prostatic ducts enter
what is the membranous urethra in the male urethra?
- shortest portion (<1cm)
- from inferior prostate gland through urogenital diaphragm
what is the spongy urethra in the male urethra?
- 15cm in erectile tissue in penis (corpus spongiosum)
- extends to external urethral orifice
in the male urethra, role of internal urethral sphincter?
prevents simultaneous passage of sperm and urine
role of female urethra?
- 3-5cm long
- only transmits urine from bladder to vestibule (external space immediately internal to labia minora)
