Urinary System Flashcards
1
Q
What always accompanies a kidney tubule in the urinary system/ “kidney”?
A
Blood vessel/capillary
2
Q
What protects the kidney within the body?
A
Kidney is surrounded by fat for protection
3
Q
Functions of kidney include
A
blood filtration, excretes waste, secretes erythropoietin, regulates calcium levels/ electrolytes, blood volume/pressure, osmolarity
4
Q
Urine is stored in _____ and made in the ______
A
Bladder, kidney
5
Q
Movement of substances from blood to kidney tubule
A
filtration
6
Q
process wherereturn of “good” substances to bloodstream, while “bad” substances gets excreted in urine
A
Absorption
7
Q
Functional unit of kidney; can make urine
A
nephron
8
Q
Formation of urine begins in this process
A
Filtration
9
Q
Each afferent arteriole has an accompanying
A
nephron
10
Q
Balls of capillaries reform into
A
efferent arterioles
11
Q
Which arterioles will be under high pressure & why?
A
Efferent arterioles due to filtration
12
Q
nephron composed of _____ that filters blood & _______ that converts filtrate into urine
A
renal corpuscle; renal tubule
13
Q
Podocytes are located in
A
Visceral layer of glomerulus
14
Q
Specialized cells that wrap around glomerular capillaries to support capillary wall
A
podocytes
15
Q
Examples of nitrogenous waste
A
Urea, Uric Acid, Creatinine, Ammonia
16
Q
Nitrogenous waste mainly excreted by humans
A
Urea
17
Q
Nitrogenous wastes that are both secreted and reabosrobed
A
Urea & Uric Acid
18
Q
Nitrogenous waste thats only secreted and NOT reabsorbed
A
Creatinine
19
Q
Engaged in active transport of salts, has lots of mitochondria & uses lots of ATP
A
Nephron Loop
20
Q
Flow of Glomerular Filtrate
A
Glomerular Capsule, PCT, nephron loop, DCT, Collecting Duct, Papillary Duct, Minor Calyx, Major Calyx, Renal Pelvis, Ureter, Urinary Bladder, Urethra
21
Q
What happens when filtrate reaches collecting duct?
A
It can be considered Urine
22
Q
Kidney converts blood to urine in 4 stages
A
Glomerular Filtration, Tubular Resorption, Tubular Secretion, Water Conservation
23
Q
Stage where filtrate is first made in urine conversion
A
Glomerular Filtration
24
Q
Plasma-like like filtrate of blood where the movement of substances from blood goes into capsular space
A
Glomerular Filtration
25
process of reclaiming water and solutes from tubular fluid and returning them to the blood in this stage of urine formation
Tubular Reabsorption
26
Removes additional waste from blood & adds it to filtrate in this process or urine formation
Tubular Secretion
27
Water is removed from urine & goes back into blood in this stage of urine formation
Water conservation
28
Filtrate is produced in this region
Renal Corpuscle (between glomerulus and Bowman's capsule)
29
Kidney is composed of how many nephrons?
1.2 million
30
What area is the cut off of a nephron?
Distal Convoluted Tubule. (DCT)
31
Beginning of nephron_____ & end of nephron ______
Renal Corpuscle; Distal Convoluted Tubule
32
nephron connected to a collecting tube that drips
urine
33
What ultimately needs to be reabsorbed from filtrate in DCT & collecting tube?
W A T E R
34
Tubular Reabsorption routes include
Transcellular (right through PCT cell) & Paracellular (right PCT between cells)
35
85 % of capillaries whose efferent arterioles branch into peritubular capillaries that surround PCT & DCT
Cortical nephrons
36
15 % of capillaries w/ long nephron loops whose efferent arterioles branch into vasa recta surrounding nephron loops
Juxtamedullary Nephrons
37
Sympathetic innervation effect on renal system
reduces glomerular. blood flow, reduces rate or urine production, responds to fall in BP by stimulating the kidneys to secrete renin
38
Substances that pass through filtration membrane
Water, Electrolytes, Glucose, Amino Acids, Fatty Acids, Vitamins and Urea
39
Substances that cannot pass through membrane
blood cells, plasma proteins
40
Sympathetic innervation & renal epinephrine cause
constriction of afferent arterioles, reduces GFR & urine output
41
Filtrate is formed when
blood flows from glomerulus , gets filtered
42
When blood plasma is forced across filtration membrane under pressure, what is formed?
Filtrate
43
Filtration membrane includes
endothelium, basement membrane and filtration slits.
44
Filtration Membrane Area that blocks formed elements (not filtered)
Endothelium
45
Filtration Membrane Area that blocks large proteins (limited filtered)
Basement membrane
46
Filtration Membrane Area that blocks small proteins (freely filtered)
Filtration Splits
47
Amount of force of pressure pushing out of capillary into filtration space
10 mm hg- net filtration pressure
48
Net Filtration Pressure proportional to
GFR, amount of filtrate formed, solutes and water remaining in tubular fluid, substances in urine
49
Net Filtration rate inversely proportional to
filtrate reabsorption
50
Amount of filtrate produced by both kidneys each minute
Glomerular Filtration Rate (GFR)
50
Amount of filtrate produced by both kidneys each minute
Glomerular Filtration Rate (GFR)
51
Average Daily GFR made by man
180 L/day
52
Average Daily GFR made by woman
150 L/D
53
99 % of filtrate is reabsorbed, because
only 1-2 L of urine is excreted daily
54
If GFR is too high
Urine output rises, fluid will not be reabsorbed properly, possible dehydration
55
if GFR is too low
waste are reabsorbed , blood is not being purifired
56
GFR is regulated by
Glomerular Blood Pressure
57
ability for kidneys to regulate their own GFR despite changes in systemic blood pressure
Renal autoregulation
58
Two methods of renal autoregulation
Myogenic and Tubuloglomerular Feedback
59
A form of renal autoregulation, the myogenic mechanism is based on
whether the arteriole wall smooth muscle contracts or relaxes when stretched
60
In the myogenic mechanism, if arterial BP raises
afferent arterioles will stretch and constrict, & prevents blood flow into glomerulus from changing
61
In the myogenic mechanism, if arterial BP decreases,
afferent arteriole will relax, and dilate. blood flow into glomerulus will increase & filtration will remain stable
62
This mechanism helps maintain normal glomerular blood pressure via the detection of NaCl in the fluid, when the myogenic mechanism fails to maintain normal glomerular blood pressure
Tubuluoglomerular Feedback Mechanism
63
When GFR is too high,
more NaCl is in the filtrate (detected by Tubuloglomerular feedbaack)
64
Increase of NaCl in filtrate/tubular fluid is detected by macula densa cells causing
macula densa cells to secrete ATP
65
Mesangial cells turn ATP into Adenosine , then
Adenosine causes granular cells to contract, which reduces blood flow through afferent arteriole and slows GFR
66
If GFR rises, more NaCL is reabsorbed & granular cells cause ....
afferent arteriole to contract causing GFR to drop to normal
67
If GFR falls, macula densa cells RELAXes afferent arteriole/ mesangial cells
blood flow increases & GFR rises to normal level
68
Renin- Angiotensin Mechanism responds to
drop in Glomerular BP, which stimulates sympathetic nervous system
69
If Glomerular Blood Pressure drops,
GFR will decrease and suffer, as it will not be able to produce enough filtrate
70
When glomerular blood pressure drops & triggers sympathetic nervous system,
the kidneys are triggered to release Renin, which converts INACTIVE angiotensinogen to ANGIOTENSIN
71
How does Angiotensin 1 turn into Angiotension 2?
ACE enzyme conversts A1 to A2
72
What does Angiotensin 2 ultimately cause?
Vasoconstriction, which increase blood pressure & GFR
73
Angiotensin 2 stimulates adrenal cortex to produces
Aldosterone
74
Aldosterone causes
NaCl AND WATER to be reabsorbed into body system; reabsorption of water increases Blood volume & blood pressure
75
Where salt goes,
water follows
76
How much glomerular filtrate is reabsorbed and by what?
65 % of glomerular filtrate is reabsorbed by PCT
77
What takes up the reabsorbed fluid once tubular reaborption occurs?
Peritubular Capillaries
78
What is solvent drag?
Water "dragging"/ taking anything that dissolves in it
79
Why is Sodium the key to reabsorption?
It creates a gradient that allows for reabsorption of water & solutes; favors diffusion into epithelial cells
80
Transporter proteins responsible for Sodium uptake
Symport (NA binds to other molecule & moves in same direction) & Antiport (pulls NA into cell & pumps H into tubular fluid)
81
Sodium Reabsorption
NA prevented from accumulating in epithelium by NA/K pump, so NA is picked up by peritubular caps & sent to blood
82
Na/K pump is an example of active transport
bc they use ATP
83
Sodium-Glucose Transporter Proteins (symport)
Sodium co transports glucose providing energy for glucose to move from tubular fluid to capillary (normally all glucose is reabsorbed)
84
Where does Tubular Reabsorption take place?
Proximal Convoluted Tubule
85
How does glucose leave cell during reabsorption?
Facilitated Diffusion
86
How do we rid Sodium out of cell during reaborption?
Na/K pumps remove excess NA. Sodium out of cell and puts K back in cell , which restores NA battery
87
How do H+ protons end up being excreted by Urine?
Na/H+ antiport- Na gradient pushed NA into cell, and H+ pushes out to tubular fluid to be excreted by urine
88
Sodium Potassium pumps use a lot of
ATP
89
Purposes of secretion in PCT and nephron loop include (2nd round filtration)
acid base balance, waste removal, clearance of drugs/contaminants
90
Nephron Loop Function
reabsorb water and sodium chloride from the filtrate which conserves water & produces highly concentrated urine.
91
allows water to move through membrane
aquaporin
92
The deeper you go into the medulla
substances get more concentrated & draws more water to be reabsorbed by capillaries
93
DCT & Collecting Ducts reabsorb water & salts & are regulated by
hormones like aldosterone, natriuretic peptide, and ADH
94
Two types of cells in DCT and Collecting ducts
prinicipal cells (most numerous, have hormone receptors, involved inwater/ salt balance) AND intercalated cells (involved in acid- base balance; Secres H+/ reabsorbs K+)
95
Salt retaining hormone; triggered when Sodium concentration fails
Aldoesterone
96
Hormone that's secreted in response to high blood pressure; ultimately secretes more Sodium & water, lowering blood pressure
Natriuretic Peptide
97
Hormone that makes collecting ducts more permeable to water by increasing aquaporins; prevents urination , takes water back to blood stream
ADH (antidiuretic hormone)
98
Part of nephron that completes the process of making urine
DCT
99
_______ conserves water
Collecting Duct
100
Part of nephron that reabsorbs Na+, Cl−, and water under hormonal control, especially aldosterone and ANP
DCT
101
NORMAL DAILY URINE VOLUME
1-2 L
102
Excess urine output (2+L/day)
Polyuria
103
Less output (500mL/day)
Oliguria
104
0-100 mL/day (which is deadly)
Anuria, which can lead to azotemia
105
Too much nitrogren in blood
Azotemia
106
Common diuretics include
Caffeine, Alcohol (inhibits ADH secretion)
107
tube that conveys urine out of body
Urethra
108
the act of urinating
Micturition
109
Renal ________ 4x more salty than renal ______
medulla; cortex
110
An active process occurring in the loops of Henle that is responsible for the production of concentrated urine in the collecting ducts of the nephrons.
Countercurrent multiplier
111
What acts as a countercurrent multiplier?
Nephron Loop
112
This is formed by blood flowing in opposite directions in adjacent parallel capillaries
Countercurrent System
