Week 9 - How do we get rid of toxic wastes? Flashcards
Which cavity are the kidneys located within?
abdominopelvic
Renal capsule
fibrous connective tissue surrounding each kidney
Adipose tissue
engulfs renal capsule and acts as cushioning
Renal fascia
thin layer of loose connective tissue which anchors kidney to posterior abdominal wall
Hilum
renal artery and nerves enter and renal vein and ureters exit
Renal sinus
hilum opens into it, filled with fat and loose connective tissue
Ureter
exists at hilum, connects at urinary bladder
Cortex
outer area
Renal columns
part of cortical tissue that extends into medulla
Medulla
inner area, surrounds renal sinus
Renal pyramids
cone-shaped, base is boundary between cortex and medulla
Renal papilla
apex of renal pyramid
Minor calyces
funnel-shaped chambers into which papillae extend
Major calyces
converge to renal pelvis
Pelvis
enlarged chamber formed by major calyces
What are the type types of nephron?
Juxtamedullary: renal corpuscle located near medulla, long loop of Henle which extends deep in medulla
Cortical: renal corpuscle located nearer to periphery of cortex, loops of Henle do not extend that deep
What is the renal corpuscle comprised of?
Bowman’s capsule: enlarged end of the nephron, double-walled, filters blood
Glomerulus: ball/network of capillaries
Afferent (into) and efferent (away from) arterioles
What are the layers of the Bowman’s capsule?
Parietal: outer layer, simple squamous, becomes cuboidal in PCT
Visceral: inner, specalised podocytes (wrap around glomerular capillaries, facilitate filtration)
Filtration membrane
Fenestrae: window-like openings in endothelial cells f glomerular capillaries
Filtration slits: gaps between podocytes
Basement membrane: sandwiched between endothelial cells of glomerular capillaries and podocytes
Renal tubules
Proximal convoluted tubule: filtrate drains from Bowman’s capsule to PCT
Loop of Henle: descending and ascending loop
Distal convoluted tubule: shorter than PCT
Collecting ducts: large diameter, medulla –> renal papilla –> ureter
Proximal tubule
simple cuboidal, microvilli
Loop of Henle
thick = simple cuboidal, thin = simple squamous
Distal tubules
simple cuboidal , few microvilli
Collecting ducts
large in diameter, simple cuboidal epithelium
How does urine move through the nephron?
- pressure and peristalsis
- pressurein bladder compresses ureters and prevents backflow
Ureters
bring urine from renal pelvis to urinary bladder, lined by transitional epithelium
Bladder
hollow muscular container, located in pelvic cavity posterior to symphysis pubis
Trigone
interior of urinary bladder, triangular area between entry of two ureters and exit of urethra
Urethra
transports urine from bladder to the outside of the body
- internal urinary sphincter - elastic connective tissue and smooth muscle prevent urine continuously flowing out of bladder
- external urinary sphincter - skeletal muscle surrounds urethra as it extends through pelvic floor
