The urinary system and Renal physiology (chapter 25) Flashcards
1
Q
how much fluid filtered from blood by kidneys every single day?
A
200 liters
2
Q
Maintaning the composition of the body’s extracellular fluids by filtering the blood. This involves
* regulating total body water volume and concentration of solutes in water
* regulate concentration of ions in ECF
* acid-base balance
* remove toxins, metabolic wastes and foreign substances
* hormone production -EPO(RBCs) and Renin(blood pressure)
A
kidneys
3
Q
true or flase:
Kidneys are retroperitoneal organs
A
True
4
Q
ureters, renal blood vessels, lymphatics, and renal nerve supply enter here
A
renal hilum
5
Q
sits immediatley superior to each kidney
A
adrenal gland
6
Q
- dense connective tissue
- anchors kidneys to surrondings structures, prevents spread of infection
A
renal fascia
7
Q
- fat mass surrounding kidneys
- cushions kidneys from physical trauma, layer of adipose tissue that surrounds each of the kidneys. Kidneys are vulnerable to physical trauma since they are not near bone so adipose tissue helps in absorbing shock
A
perirenal fat capsule
8
Q
- thin, transparent capsule
- prevents disease from spreading to kidneys from other parts of body
A
Fibrous capsule
9
Q
- provides area for glomerular capillaries and blood vessel passage, EPO produced here
- glomerular capillaries are responsible for filtrate which is the first step in urine formation
- EPO stimulates rbc production
A
Renal cortex
10
Q
- contains renal pyramids–> packed with capillaries and urine collecting tubules
- seven renal pyramids separated by renal columns
- renal pyramids + surrounding columns=kidney lobe
A
Renal Medulla
11
Q
- open space in center of each kindey
- Branches to form Major/Minor calyces
A
Renal pelvis
12
Q
- urine collection from renal medulla
- pathway to get urine from renal pyramid out of kidneys towards the bladder
A
Major/Minor calyces
13
Q
- deliver to kidneys, divde into smaller blood vessels to serve major regions of kidneys
A
renal arteries
14
Q
deliver blood to higher and lower secretions of kidneys
A
segmental arteries
15
Q
travel between kidney lobes
A
interlobar arteries
16
Q
arch over bases of pyramids
A
arcuate arteries
17
Q
supply cortical tissue
A
cortical radiate arteries
18
Q
True or false
veins trace arterial supply but in reverse
A
true
19
Q
autonomic nerve fibers and ganglia
A
renal plexus
20
Q
has control over blood vessels
A
sympathetic division
21
Q
adjusts diameter of renal arterioles to adjust blood flow to glomeruli
A
sympathetic vasomotor fibers
22
Q
- functional unit of the kidney
- responsible for forming filtrate and eventually urine in the kidneys
A
Nephron
23
Q
each nephron contains a
A
renal corpuscle and renal tubule
24
Q
- filters blood to form filtrate
- located in the renal cortex
A
renal corpuscle
25
reabsorbs what is needed for the body from the filtrate and secretes more substances into the filtrate
renal tubule
26
cluster of blood vessels
glomerulus
27
blood enters glomerules via.....and leaves via.....
* afferent arterioles
* efferent arterioles
28
True or false
capillaries are very porous
true
29
double layered structure that completely surronds glomerular capillaries
glomerular capsule
30
The glomerular capsule inner layer has 2 structures
Podocytes and foot processes
(There is not a lot of open space between processes it prevent large size substances from entering the filtrate)
31
begins in the renal cortex and extends into renal meduall, then returns to renal cortex
-the hairpain structure helps increase surface area which is more affective
renal tubules and collecting ducts
32
* leads immediatley off from glomerulus
* located in renal cortex
* large cuboidal epithelia cells with dense microvilli
* microvilli increases absorption and secretion
Proximal convoluted tubule (PCT)
33
* travels between renal cortex and renal medulla
* allows the kidney to vary the concentration of urine according to how much water is reabsorbed
nephron loop
34
* portions continuous with PCT
* high permeability to H20, low permeability to solutes
* water can cross wall of descending limb but solutes cannot
descending limb
35
* continuous with DCT
* high permeability to solutes, low permeability to H2O
* solutes can cross wall of ascending limb, but water cannot
Ascending limb
36
* located in cortex, composed of small cuboidal epithelia
* smaller diamter than PCT, contain no microvilli
Distal convoluted tubule (DCT)
37
* pass through cortex and medulla
* waste goes through
* receives filtrate from tubules of multiple nephrons
collecting ducts (collecting ducts fuse together, dump urine into minor calyces)
38
2 important cell types in collecting duct
Principal cells and intercalated cells
39
* maintain Na+ balance in body
* influence absorption of water
Principal cells
40
Helps maintain acid-base balance
Intercalated cells
41
* located almost entirely in the cortex
* small portion of nephron loop found in renal medulla
Cortical Nephrons
42
* Nephron loops deeply invade renal medulla
* have a longer nephron loop so its more useful to form highly concentration urine
* better ar reabsorbing water
Juxtamedullary Nephrons
43
* maintains high pressure to increase filtrate production
* Fed and drain by arterioles to keep high pressure
Glomerulus
44
* low pressure capillaries arising from efferent arteriole (want low pressure since it allows as much reabsorption as possible)
* cling to proximal and distal tubules of cortical nephrons (reabsorbs water and solutes from tubule cells)
* empty in venules--> filtered blood returns to circulation
Peritubular capillaries
45
* found only on juxtamedullary nephrons
* run parallel to long nephron loop
* forms more concentrated urine
vasa recta
(The more the vasa recta reabsorbs water from nephron loop= the more concentration the urine/filtrate will be)
46
* portion of nephron where distal ascending limb lies against arterioles
* regulate blood pressure and filtration rate of the glomerulus
Juxtaglomerular complex
47
* chemoreceptor cells
* monitor NaCl content of filtrate entering distal convoluted tubule
macula densa
48
* specialized smooth muscle cells
* found in arteriolar walls of afferent arteriole
* can sense blood pressure in afferent arteriole
* have baroreceptors
* secrete renin
granular cells
49
low NaCl concentration...
increases renin release
50
* packed between tubule and arterioles
extraglomerular mesangial cells
51
allows passage of water, small solutes into glomerular capsule
Filtration membrane
52
pores in capillary walls allow all but large proteins and cells to pass through (allows fluid to squeeze through, but pores are small enough to not let large proteins in)
fenestrated endothelium of capillaries
53
negatively charged layer that allows only passage of small molecules and electrically repels other macromolecular anions
basement membrane
54
* foot processes create filtration slits
* slits prevent passage of macromolecules/large sized materials into filtrate
Foot processes of podocytes
55
pressure that force fluid into or out of glomerulus
filtration pressure
56
* promotes filtrate formation
* fluid moves from capillary into glomerular capsule
outward pressure
57
blood pressure of the glomerular capillaries that forces fluid into the surrounding space
Hydrostatic pressure in glomerular capillaries
58
* oppose filtrate formation
* fluid moves from glomerular capsule and into glomerular capillary
inward pressure
59
pressure exerted by filtrate that is already in the glomerular capsule
hydrostatic pressure in capsular space
60
* proteins that are still in capillaries will "pull" water back in
* always have a net pressure on 10 mmHg
Colloid osmotic pressure in glomerular capillaries
61
the total volume of filtrate formed per minute for all nephrons in the kidney-125 mm filtrate per minute
Glomerular Filtration rate
62
Increase of decrease the 10 mm HG then you either forming more or less filtrate
Net filtration pressure
63
adjust surface area of capillaries
-contraction will cause less surface area-->decreasn filtration formation
Glomerular mesangial cells
64
kidneys adjust resistance to blood flow
renal autoregulation
65
smooth muslce contracts when stetched
Myogenic mechanism
66
controlled by Macula densa of juxtaglomerular complex (JGC)
Tubuloglomerular Feedback Mechanism
67
The sympathetic nervous system will override renal autoregulation
Neural Mechanisms (extrinsic)
68
* overall affect is to increase blood pressure
* granular cells of JGC stimulated to release renin
renin Angiotensin Aldosterone mechanism (hormonal Mechanism)
69
substances move in between kidney tubule cells
paracellular
70
substances move through kidney tubule cells
transcellular
71
collecting ducts have no aquaporins until.... is present
ADH (antiduretic hormone)
72
Any pathway using a transport potein has a
transport maximum (Tm)
73
* inhibits urine formation by increasing water reabsorption to blood
* directly proportional to number of aquaporins inserted
Antidiuretic hormone (ADH)
74
* promotes Na+ reabsorption by principal cells of collecting ducts
Aldosterone
75
inhibits Na+ reabsorption in collecting ducts
Atrial Natriuretic peptide (ANP)
76
Increase reabsorption of calcium in the DCT
Parathyroid hormone (PTH)
77
* selectively moving substances from the blood and back in the filtrate
* main site is PCT
secretion
78
the normal solute concentration of body fluids and ICF is...
300 Mosm
79
movement of fluids in the opposite direction through the nephron loop allows exchange of material
countercurrent exchange mechanism
80
* occurs in ascending and descending limb of juxtamedullary nephron loops
* movement of solutes and water out of nephron loop allows for formation of concentrated urine
countercurrent multiplier
81
* flow of blood through the ascending and decending limb of the vasa recta
* vasa recta reabsorbs water to maintain gradient of multiplier
countercurrent exchange
82
* countercurrent exchange mechanism establishes a .....
* kidneys can vary urine concentration
Meduallary Osmotic Gradient
83
* GFR of <60 ml/min for 3+ months
* filtrate formation decreases--> wastes build up, blood pH decreases
* caused by: diabetes mellitus, hypertension, pyelonephritis, physical trauma
Chronic renal disease
84
* "urine in the blood" (nausea,muslce cramps, mental changes, fatigue etc)
uremia
85
patients blood passed through selectively permeable membrane tubing
Hemodialysis
86
color of urine comes from presence of...
urochrome
87
the ratio of mass of a substance to the mass of an equal volume of distilled H20
Specific gravity
88
Tubes that allow urine to pass from the kidneys to be stored in the bladder
Ureters
89
what are the 3 layers of the ureter?
1. Mucosa
2. Muscularis
3. Adventitia
90
* Build up calcium, magnesium salts and uric acid in kidneys
* severe abdominal pain, nausea and vomiting, cloudy/foul-smelling urine
Renal Calculi (Kidney stone)
91
Stones can remain lodged in the renal pelvis
Nephrolithiasis
92
Stones can become lodged in the ureter
Ureterolithiasis
93
* found in abdominopelvic area
* stores urine temporarily
* .... has three openings
* Bladder
* Trigone
94
Human bladder normally holds up to...
400-500 ml of urine
95
critical capacity of urine
1000ml urine
96
* Extends from bladder, leads out of body
urethra
97
* thickening of detrusor muslce
* closes urethra when urine is not being passed
Internal urethral sphincter
98
* closes urethra when urine is not being passes
internal urethral sphincter
99
....also helps close off urethra (contracts with more force when your legs are closer tg)
Levator ani muscle
100
the act of empyting the bladder
micturition
101
Control of micturition:
pons has
Potine micturition center and Pontine Storage center
102
* Anything that enhances urine output
Diuretics
