Urinary Flashcards
organs of urinary system:
- 2 kidneys
- 2 ureters = carry urine from kidneys to bladder
- 1 bladder
- 1 urethra = carries urine from bladder to the outside of the body
- kidneys are located:
behind the peritoneal membrane, near the lateral posts muscle
- renal capsule
layer of adipose/fibrous connective tissue; cushions the kidneys against mechanical shock
- parietal fat pad (adipose)
engulfs renal capsule acts as cushioning
- renal fascia
thin connective tissue surrounds the adipose tissue and help anchor the kidneys to abdominal wall.
urine flow path
- minor calyces
- major calyces
- renal pelvis
- ureters
- urinary bladder
- urethra
afferent / efferent
affarent = sensory neurons that carry nerve impulses from sensory stimuli towards the central nervous system efferent = motor neurons that carry neural impulse away from the central nervous system and towards muscle to cause movement
muscle in afferent and efferent arterioles
smooth muscle
external urinary sphinkter:
controls flow of urine through urethra
effect of ADH
- increase kidney reabsorption
- increase in number of aquaporins=membrane protein transfer water
- decrease in blood osmolarity
renal fraction
potion of total cardiac output flows through the kidneys
Function of Kidney
- excretion
- regulation of blood volume
- regulation of the concentration of solutes in the blood: Na+, Cl-, K+, Ca2+, HCO3-, HPO4 2-
- regulation of extracellular fluid pH = secrete variable amount of H+
- regulation of red blood cell synthesis = secrete hormone erythropoietin which stimulate RBC in red bone marrow
- regulation of vitamin D synthesis
nephron
Function:
Regulate concentration of water and substances (Na) by filtering blood, reabsorbing what is needed, excreting the rest as urine
consists of 4:
- renal corpuscle
- proximal convoluted tubule
- loop of Henle (nephron loop)
- distal convoluted tubule
major ions regulated by kidney:
- chloride Cl+
- bicarbonate HCO3-
- phosphate PO
- sodium Na+
renal pelvis
- major calyces converge to form enlarged chamber
- surrounded by renal sinus
bladder
locate in pelvic cavity posterior to the symphysis pubis
Store urine and drain into urethra
filtration:
- positively charged ions -
- proteins less than 7nm -
- most blood cells
- pass freely into filtrate (dissolved ions)
- small amounts may enter the filtrate but will ultimately be reabsorbed
- cannot pass into filtrate
impermeable to filtration barrier:
- proteins
- blood cells