Urinary System Flashcards
metabolic waste products
products not needed by the body anymore, include potentially harmful substance that must be eliminated and can be harmful if accumulated
kidneys
located in the dorsal abdominal area; right kidney is more cranial than left
retroperitoneal
Between the peritoneum & the abdominal cavity
urinary system functions
Production of urine; maintain homeostasis through blood filtration, reabsorption & secretion; fluid base regulation; acid base balance regulation; production of hormones; blood pressure regulation
Nerve supply to the kidney
Sympathetic stimulation causes vasoconstriction of renal vessels; sympathetic portion of autonomic nervous system releases norepinephrine
Kidney hormones
ADH, aldosterone, erythropoietin, prostaglandins, & rentin
Renal capsule
Thick fibrous covering of the kidney
Hilus
Indented area where ureter, renal artery, renal vein & nerves enter & leave
Renal cortex
Outer portion of the kidney, reddish brown in color
Renal medulla
Surrounds renal pelvis; drains urine to calyces
Calyces
Direct urine into renal pelvis, from there urine moves into ureter
Renal pelvis
Urine collection chamber that forms beginning of ureter; not present in cow; lined with transitional epithelium for stretching
Mutilobar/multi pyramidal
Numerous medulla a facing the ureter; cows & pigs
Unipyramidal/ unilobar
Medullary pyramids fused as 1 structure to form a calyx that directs urine into renal pelvis
Nephron
Basic functional unit of the kidney
Afferent arterioles
Carry blood to renal corpuscle
Renal corpuscle
Located in the cortex, made up of the glomerulus & bowmen’s capsule
Glomerulus
Tuft of capillaries where filtration starts; forms glomerular filtrate
Bowmen’s capsule
Double walked capsule that surrounds glomerulus with visceral & parietal layers
Podocytes
Extensions that cover glomerular capillaries with a permeable layer to allow fluid & dissolved substances to pas through
Proximal convoluted tubule
Continuation of capsular space of bowmen’s capsule; longest part of nephron; reabsorption & secretion of tubular filtrate
Efferent arterioles
Carry blood out of renal corpuscles
Peritubular capillaries
O2 exchange to cells of nephron; reabsorption & secretion
Loop of henle
Continues from PCT, descends into medulla, makes a u turn & heads back into cortex; ascending wall becomes thicker again
Distal convoluted tubule
Continuation of ascending loop of henle; empties into collecting ducts
Collecting ducts
Hold urine; empty into renal pelvis; primary site of ADH action & regulation of K, Na & acid-base balance
Blood flow through the kidney
Renal artery ➡️ afferent arterioles ➡️ glomerulus capillaries ➡️ efferent arterioles ➡️ peritubular capillaries ➡️ renal vein
Renal artery
Branches off abdominal aorta & brings blood to the kidney
Renal vein
Takes purified blood from the kidney & brings it to the caudal vena cabs
Fenstrations
Windows in capillary endothelium
Urine volume regulation
Controlled by the action if ADH & aldosterone
Ureters
3 layers
Outer fibrous
Middle muscular
Inner epithelial
Trigone
Oblique angle where ureters insert into the bladder
Urinary bladder
Where urine is stored as its produced
Detruser muscle
Smooth muscle of the urinary bladder that contracts to expel urine
Circulator sphincter muscle
Around the neck of the bladder to provide voluntary control over urination process
Control of urination
Urine accumulation
Detruser muscle contraction
Circulator sphincter muscle control
Release of urine
Urethra
Continuation of the neck of the bladder
Urachus
Tube that runs from the fetal bladder to the umbilicus vein
Waste products include
Water, urea, salts &a other soluble waste products
