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Definition
temporarily stores urine produced from the kineys |
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Definition
permits urine flow from kidneys to bladder |
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Definition
transports urine from bladder to exteriour of body |
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Definition
urine production and maintaining homeostasis |
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Definition
posterior abdominal wall, ouside the peritoneal cavity. Each kidney lies on either side of the vetebral column, extending from the 12th thoracic vetebrae to the 3rd lumbar vetebrae. |
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Definition
cleft in the middle of the concave surface of the kindeys. It is the area where blood vessels, nerves and joining tubes to the bladders are connect to the kidneys |
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Definition
layer of fibrous connective tissue that encapsulates each kidney. It is embedded in a mass of fat |
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Definition
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medulla location and structures |
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Definition
forms the inner layer of kidneys. Consist of regions called pyramids. renal column between each pyramid divides each pyramid. The papillae are the inward projection of the pyramids. Pyramids extends into the renal pelvis . |
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Definition
connects to ureters to allow urine to flow to bladder |
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major and minor calyces functions |
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Definition
chambers recieving urine. Also, form entry of renal pelvis |
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two layers of the glomuruler capsule and types of cells they consist of |
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Definition
-visceral (inner layer): specialised epithelial cells called podocytes
-parietal (outer layer): simple squamous epithelial cells |
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Term
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Definition
specialised cells in visceral layer of glomeruler capsule. Allow th movement of fluids from capillaries and into the capsule |
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Term
name two major nephrons and their location |
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Definition
-juxtamedullary: lie close to and extend deep into the medulla
-cortical: makes up ~85% of nephrons. Located in cortex and extend only partially to the medulla |
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Term
importance of juxtamedullary nephrons |
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Definition
important for kidney production of concentrated urine |
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Term
amount of blood needed for kidneys |
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Definition
25% of CO, or 1000-1200mL blood/min |
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Term
location of juxtaglomeruler apparatus |
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Definition
Located around the afferent arteriole, where it enters the renal corpuscule |
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Term
two parts of juxtaglomeruler apparatus and their function |
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Definition
1) Juxtaglomeruler cells: specialised cell that release a hormone called renin. They detect BP within the kidneys, contain granules that secrete renin when stimulated.
2) macula densa: detect sodium levels within the distal tubules |
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Term
Two factors the juxtaglomeruler apparatus controls |
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Definition
Important in sensing the properties of fluid flowing though the region (at entry of arteriole). the apparatus controls BP and glomerular filtration rate |
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Term
processes of urine formation |
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Definition
glomerular filtration
glomeruler reabsorption
glomeruler secretion |
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Term
how do fluids and solute move across the glomerular filtration membrane |
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Definition
fluids and solutes are forced across the GF membrane by hydrostatic pressure |
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Term
What should not cross the glomeruler filtration membrane |
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Definition
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Term
compare glomeruler filtration to other capillaries |
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Definition
membrane of glomeruler filtration is freely permeable to water and relatively impermeable to large compounds (like other capillary membranes). The glomerulus has a higher pressure than other capillaries and have structures called fenestrations. This makes the glomerulus more effiecient in filtering at a faster rate than other capillaries |
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Term
the major force in the capillaries in the glomeruler capsule |
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Definition
-hydrostatic pressure: major force for moving water and solutes across the filtration membrane and into the glomeruler capsule
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Term
the 2 opposing the filtration effects of the glomeruler hydrostatic pressure |
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Definition
-hydostatic pressure in glomeruler space
-oncotic pressure of the glomeruler capillary blood |
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Term
hydrostatic pressure (glomeruler) |
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Definition
pressure moving water and solutes from the glomerulus into the glomeruler capsule |
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Term
5 processes in which tubular reabsorption can take place |
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Definition
simple diffusion, facilitated diffusion, osmosis, active transport and co-transport |
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Term
describe pressure in the peritubular capillaries |
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Definition
pressure in the peritubular should be low, so that filtrate may be reabsorbed from the tubules |
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Term
describe process of glucose reabsorption |
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Definition
glucose reabsorption is via co-transportation. Specific protein carriers return filtered glucose back into the bloodstream. |
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How may co-transportation be limited in reabsorption |
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Definition
there are only a limited amount of of protein carriers avaliable |
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Term
describe relationship of tubule length and effeciency in water conservation |
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Definition
longer loop=greater the ability to concentrate urine |
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Term
Main role of the proximal convoluted tubule |
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Definition
To reabsorb sodium by active transport using the active sodium-potassium- ATP pump. This allows for other electrolytes and water to move from the PCT and into the peritubular capillaries to be brought back into the bloodstream. |
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Term
Describe co-transportation with sodium and electrolytes in the PCT |
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Definition
movement of Na by the Na-K-ATP pump to be absorbed, also allows other electrolytes (K, Cl, Ca and phosphate) to be reabsorbed |
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Term
Describe movement of water in PCT (2) |
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Definition
The Na-K-ATP pump generates osmotic force, which allows water to passively diffuse out of the PCT and into the peritubular capillaries.
Also, water transportation is enhanced by elevated oncotic pressure of blood in the peritubular capillaries |
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Term
Compare the ascending and descending arms of the loop of Henle (3) |
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Definition
(Compare: permeability, which substances transported and form of transportation)
-Descending arm: highly permeable to water, no active transport capabilities, water moves out via osmosis
-Ascending arm: non-permeable to water, allows Na to move out using active and passive transports |
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Term
Describe filtrate when it enters the distal convoluted tubule |
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Definition
the majority of water and electrolyte reabsorption have already occured. |
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Term
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Definition
Work with the collecting duct, under hormonal control to adjust solute concentration |
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Term
Describe permeability in the DCT, what hormone controls the permeability |
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Definition
Is unpermeabile to water. However the end of the DCT and collecting duct are permeable to water as controled by the hormone, antidiuretic hormone (ADH) |
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Term
How does ADH control reabsorption at the end of the DCT/collecting duct |
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Definition
Presence of ADH, water is reabsorbed from the filtrate to increase blood volume |
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Term
What happens to Na in the DCT |
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Definition
reabsobed in later segment of the DCT/collecting duct. This is under the influence of aldosterone |
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Term
What can be secreted in the later segment of the DCT/collecting duct and how |
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Definition
K may be secreted in the latter segment/ collecting ducts. This is controled by aldosterone and other fators related to regulating potassium levels in the body |
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Term
What does aldosterone control in the latter segment of the DCT and collecting duct |
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Definition
controls Na reabsorption and K secretion |
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Term
3 types of urine concentration |
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Definition
hypotonic, isotonic and hypertonic |
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Term
How is ADH released (from detecting internal changes) |
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Definition
Osmoreceptors in the hypothalamus senses changes in blood osmolity. When there is an increase in blood osmolity, ADH is released by from the posterior pituitary gland. |
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Term
What other (external) factors can cause the release of ADH |
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Definition
surgery, pain, exercise and heat exposure |
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Term
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Definition
Acts to preserve water content. ADH increases water permeability in the last segment of the DCT and collecting duct. Therefore, more water is diffused out of the tubule and returns to the systemic circulation. Urine becomes more concentrated |
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Term
ADH does not effect which electrolyte |
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Definition
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Term
Describe processes in which angiotension II is produced |
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Definition
a decrease in BP or decrease in plasma volume -> stimulates the juxtaglomeruler apparatus to release -> renin enzyme to act on plasma protein angiotensionogen (produced in liver) -> interaction changes angiotensionogen to angiotension I -> Angiotension converting enzyme (ACE, found in the capillary of lungs in lungs) converts angiotension I -> angiotension II |
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Term
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Definition
in the capillaries of the lungs |
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Term
what is renin and where is it found |
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Definition
Renin is an enzyme, which is formed and arterioles of the juxtaglomeruler apparatus |
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Three effects of angiotension II and their processes |
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Definition
- stimulate hypothalamus to release anti-diuretic hormone -> increasing water absorption -> decrease urine output
-stimulate adrenal cortex to release aldosterone -> acts on DCT and collecting ducts -> inc. Na reabsorption -> water follows -> inc. blood volume and dec. urine output
-causes vasocontriction -> inc. BP -> inc blood volume -> dec. urine output |
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Term
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Definition
by-product of protein metabolism in the liver. Excreted in kidneys |
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Term
2 factors influencing urea levels in blood rise |
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Definition
1) urea concentration increases as glomeruler fitration drops.
2) Altered protein intake and protein catabolism
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Term
3 conditions thar elevated urea levels in blood can indicate |
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Definition
dehydration, acute or chronic renal failure |
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Term
what is creatinine and why to measure |
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Definition
by-product of uscle metabolism. Released into the body at a relatively constant rate. Creatinine clearance is a good indicator to renal function |
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Term
describe normal process of micturition (micturition reflex) |
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Definition
stretch in bladder muscles, when full -> mechanoreceptors respond to stretch -> stimulates nerve impulses -> travel to sacral level of spinal cord -> action potential of parasympathetic fibres of the autonomic nervous system causes detrusor muscles of bladder to contract -> simultaneously (with detrusor movement) the internal urethral sphinter relaxes -> individual feels urge to void |
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Term
what may inhibit the relaxation of the external urethral sphinter |
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Definition
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Term
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Definition
controls the micturition reflex |
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Term
location of bladder (in females and males) |
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Definition
in the pelvic cavity, behind the symphysis pubis.
females: anterior to vagina and uterus
males: anterior to rectum |
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Term
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Definition
spinal reflex: co-ordinates the signals of the micturation process |
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Term
describe conscious desire to urinate |
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Definition
when mechanoreceptors signal to sacral area (PNS), signals are also sent to the pons and cerebrum. Allowing individual to have conscious control over urination |
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Term
consciously inhibit urination |
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Definition
brain sends signal via efferent pathways to spinal cord and micturation reflex is inhibited |
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Term
intrinsic control of renal system (2) |
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Definition
-renal autoregulation: keep blood flow and glomerular filtration rate constant -macula dense cells (distal convoluted tubules) of juxtaglomerular apparatus assist by sensing Na levels |
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Term
extrinsic control of renal system (2) |
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Definition
1) sympathetic nervous system 2) hormonal control |
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