Urinary System Flashcards
Structures in urinary system
- kidneys (2)
- ureters (2)
- urinary bladder
- urethra
Functions of urinary system
regulates blood volume and pressure, pH, ion concentrations and eliminates wastes
Position of kidneys
retroperitoneal and right kidney lower than left
Kidney is protected by the..
renal capsule which is adipose tissue and renal fascia
Renal hilus
medial indentation, entry point of renal artery, renal vein, ureter and nerves
Renal artery is
superior
Renal vein is
inferior
Internal anatomy of kidneys contain
- renal cortex (superficial)
- renal medulla
Renal medulla contains
-renal pyramids (6 per kidney)
Renal pyramids narrow end is called..
apex of pyramid or renal papilla
Renal columns
separate pyramids, contain blood vessels
Nephron
functional unit of kidney (microscopic)
Nephron composed of
renal corpuscle and renal tubules
Renal corpuscle
in cortex, site of blood filtration and first step in urine formation
Parts of the renal corpuscle
- glomerulus
- Bowman’s capsule
- filteration membrane
Glomerulus
= capillary bed
Bowman’s capsule
surrounds glomerulus, collects filtration from glomerulus
2 layers of Bowman’s capsule
- outer =simple squamous epithelium
- inner =podocytes wrapped around glomerular capillaries
Filteration membrane consists of
- glomerular endothelium
- basement membranes
- podocytes
Glomerular endothelium (capillaries)
simple squamous with pores
Podocytes
(of Bowman’s capsule) simple epithelium, projections blind to glomerulus
3 parts of the renal tubules
- proximal convoluted tubule
- loop of henle
- distal convoluted tubule
Proximal convoluted tubule
(PCT) in cortex
Loop of henle
descending and ascending limbs, in medulla
Distal convoluted tubule
(DCT) in cortex
2 types of nephrons
- cortical (85%)
- juxtamedullary (15%)
Cortical nephrons
renal corpuscles near kidney surface in cortex, short loop of henle in outer medulla, composed of peri tubular capillaries
Juxtamedullary nephrons
renal corpuscules in cortex very close to medulla
Juxtamedullary have long..
loops which penetrate deep into medulla which also allows concentration of urine depending on need, contain peri tubular capillaries and vasa recta
Juxtaglomerular specifically allow for the ..
concentration and dilution of urine
Parts of the juxtaglomerular complex
- tubular portion
- arteriolar portion
Tubular portion of juxtaglomerular complex
modified (tall and narrow) ascending limb cells (macular densa)
Arteriolar portion of juxtaglomerular complex
afferent and efferent artiolar portion (granular)
Arteriolar portion’s function of juxtaglomerular complex
monitor blood pressure and contain renin
Ureters histology
- mucosa
- muscularis externa
- adventitia/serosa
Mucosa in ureters
transitional epithelium
Muscularis externa in ureters
smooth muscle with 3 layers
Ureters are..
retroperitoneal
Urinary bladder histology
- mucosa
- muscularis externa
- adventitia/serosa
Mucosa of urinary bladder
transitional epithelium with rugae
Muscularis externa of urinary bladder
=detrusor muscle
Adventitia/serosa of urinary bladder
- adventitia =anterior, posterior, inferior
- serosa= superior
Internal structure in the urinary bladder
triangle of 2 ureters and urethra openings = trigone
Internally in the urinary bladder lacks
rugae, allows opening to remain in fixed position
Urethra histology
- mucosa
- muscularis externa
Mucosa of the urethra
transitional to stratified squamous epithelium
Muscularis externs of urethra
smooth muscle
2 sphincters of the urethra
- internal urethra sphincter
- external urethra sphincter
The 2 sphincters of the urethra both..
surround proximal end of urethra
Internal sphincter of urethra
thickening of detrusor muscle at base of bladder (smooth muscle)
External sphincter of urethra
in urogenital diaphragm (skeletal muscle)
Function of urethra in females
transports urine
Function of urethra in males
transports urine and semen
