Chapter 24 - Urinary System Flashcards
1
Q
Primary functions of the US
A
formation of urine through filtration of blood
2
Q
functions of urine
A
excretion of metabolic waste, regulation of blood volume, osmolarity, and pH balance
3
Q
main type of metabolic waste secreted by urine
A
nitrogenous waste
4
Q
functions of Kidney
A
filter blood, form urine, secrete erythropoietin, calcitriol synthesis, detoxification of free radicals
5
Q
function of ureters
A
transport urine to urinary bladder
6
Q
urinary bladder function
A
stores urine
7
Q
urethra funciton
A
excretes urine from the urinary bladder
8
Q
erythropoietin
A
hormone that stimulates erythropoiesis: RBC formation
9
Q
calcitriol synthesis
A
active formation of vitamin D that raised blood calcium
10
Q
free radicals
A
atoms with an unpaired electron that are highly reactive and destructive
11
Q
example of free radical
A
oxygen radical
12
Q
nitrogenous waste
A
toxic metabolic waste through which excess nitrogen is created in the body
13
Q
types of nitrogenous wastes
A
Ammonia, Urea, Uric Acid, Creatine
14
Q
Ammonia chemical formula
A
NH3
15
Q
Urea Chemical formula
A
CO(H2)2
16
Q
ammonia is produced from
A
amino groups during protein breakdown
17
Q
urea is produced from
A
ammonia by the live
18
Q
uric acid is produced from
A
the breakdown of nucleic acids
19
Q
creatine is produced from
A
the breakdown of creatine phosphate
20
Q
blood flow through the kidney arteries
A
abdominal aorta, renal artery, segmental arteries, interlobar arteries, arcuate arteries, cortical arteries, afferent arteriole, efferent arteriole
21
Q
renal arteries
A
enter the kidney and branch into the segmented arteries
22
Q
segmented arteries
A
branch into interlobar arteries
23
Q
interlobar arteries
A
pass through renal columns and branch into arcuate arteries
24
Q
arcuate arteries
A
lie at the corticomedullary junction
25
corticomedullary junction
the border between the renal cortex and medulla that branch into cortical radiate arteries
26
cortical radiate arteries
move into the cortex and branch into afferent arterioles
27
afferent arterioles
form the glomerulus capillary bed
28
efferent arteriole
emerges from the glomerulus and branches into the peritubular capillaries or vasa recta
29
the kidney veins are the same as the kidney arteries except for
there are no segmental veins
30
renal fibrous capsule
external layer that encloses and protects the kidney
31
the renal fibrous capsule is composed of what type of tissue
collagen fiber
32
renal parenchyma
granular tissue that forms urine and encircles
33
renal sinus
cavity near the medial aspect of the kidney
34
regions of the parenchyma
cortex and medulla
35
the cortex is ____ and the medulla is _____
superficial, deep
36
renal columns
extensions of cortical tissue
37
renal pyramids
composed of nephron loops and collecting ducts
38
nephron
functional unit of kidney
39
nephron function
filters blood to form filtrate and concentrate and convert waste into urine
40
filtrate
filtered blood that enters the nephron
41
how much filtrate goes through a kidney a day
1.2 million
42
parts of the nephron
renal corpuscle and renal tubule
43
renal corpuscle is composed of
the glomerulus capillary bed and glomerulus capsule
44
function of renal corpuscle
filter blood
45
the renal corpuscle is found in
the cortex
46
glomerulus
a cluster of capillaries that delivers blood to the kidney
47
glomerulus capsule
surrounds glomerulus
48
layers of the glomerulus capsule
visceral layer, capsular space, and parietal layer
49
glomerulus visceral layer is made of
cells called podocytes surrounding capillaries
50
glomerulus capsular space
between layers of glomerulus where filtrate enters corpuscle
51
the parietal layer of the glomerulus
outer wall of the corpuscle
52
renal tubule function
forms urine from filtrate
53
parts of the renal tubule
proximal convoluted tubule, nephron loop, distal convoluted tubule, collecting duct
54
proximal convoluted tubule receives filtrate from
the Renal corpuscle
55
the proximal convoluted tubule is found in
the cortex
56
PCT shape
long and coiled
57
nephron loop receives filtrate from
the PCT
58
the Nephron Loop is where
descends into the medulla and is part of the renal pyramids
59
nephron loop shape
u-shaped
60
distal convoluted tubule receives filtrate from
the nephron loop
61
the distal convoluted tubule is found in the
renal cortex
62
the collecting duct receives urine from
multiple DCTs
63
function of the DCT
delivers urine into larger urine collecting structures
64
the collecting duct is located within
the renal pyramid
65
glomerular filtration
blood is filtered from the glomerulus and forms filtrate
66
glomerular filtration occurs in
the renal corpuscle
66
where does tubular reabsorption occur
in renal tubule
66
tubular reabsorbtion
solutes are removed from filtrate and returned to blood
67
tubular secretion
additional substances are removed from blood or added to filtrate
68
tubular secretion occurs in
the renal tubule
69
water conservation
additional substances are removed from blood or added to filtrate
70
water conservation occurs in
the renal tubule through the collecting duct
71
what is the first stage of urine formation
glomerular filtration
72
special capillary exchange that occurs in glomerular filtration
blood in the glomerulus is filtered and removed substances enter the bowman's capsule as filtate
73
filtration membrane is made of
capillary membrane, the basement membrane, and filtration slits
74
filtration membrane
fenestrations that allow substances out of the capillary
75
anything smaller than ___ nm can go through the filtration membrane
70 nm
76
basement membrane
negatively charged membrane between glomerulus and podocytes
77
what substances can filter through the basement membrane
smaller than 8 nm and neutral or positively charged molecules
78
filtration slits
spaces between feet processes of podocytes that allow substances into capsular space
79
substances become filtrate when they pass through what part of the filtration membrane
the filtration slits
80
filtrate is made of
water, glucose, amino acids, fatty acids, nitrogenous waste, salt
81
glomerular filtration rate
amount of filtration formed per minute by both kidneys
82
male average GFR
125 mL/min
83
female average GFR
105 mL/min
84
how much human blood is filtered through the kidneys each day
50-60x blood volume filtered per day
85
what percentage of filtrate is reabsorbed and returned to blood
99%
86
how much urine is excreted per day
1-2 Liters
87
what happens when GFR is too high
the filtrate flows fast through the renal tubule, preventing reabsorption, causing dehydration and excess urination
88
what happens when GFR is too low
waste is not removed from blood or reabsorbed
89
how is GFR controlled by Glomerular blood pressure?
higher G blood pressure causes high blood hydrostatic pressure, which causes high net filtration pressure, leading to high GFR
90
does Blood hydrostatic pressure favor filtration or reabsorption
filtration
91
Blood Hydrostatic pressure is high in the glomerulus because
the afferent arteriole is larger than the efferent arteriole
92
NFP = BHP - (CP+COP) =
10 mmHg
93
CP
Capsular hydrostatic pressure
94
CP favors reabsorption/filtration
reabsorption
95
COP
blood colloid osmotic pressure
96
COP favors reabsorption/filtration
reabsorption
97
renal autoregulation
nephrons adjust their own blood flow
98
myogenic mechanism
prevents sudden/short term increases in systemic BP from overly increasing GFR
99
myogenic mechanism tries to
maintain baseline
100
myogenic mechanism contracts the afferent arteriole smooth muscle when
the smooth muscle is stretched by high blood pressure
101
sudden increase in systemic BP causes what in the kidneys
1) afferent arterioles stretch due to BP and blood flow surge
2) Arterioles contract and less blood flows to the glomerulus
3) Glomerular BP and GFR lowers back to baseline
102
tubuloglomerular feedback
glomerulus receives feedback of status downstream tubular fluid and adjusts filtration rate
103
macula densa
patch of sensory cells in the nephron loop just before the Distal CT
104
macula densa detects _____ levels in filtrate
NaCl
105
high NaCl in the Macula Densa causes
high GFR and the macula densa to stimulate the juxtaglomerular cells
106
juxtaglomerular cells
modified smooth muscle cells wrapping around the afferent arteriole
107
juxtaglomerular cells constrict if stimulated by ____
the macula densa
108
vasoconstriction of afferent arteriole causes
less blood flow to the glomerulus, leading to lower glomerular BP, causing lower GFR
109
sympathetic control of afferent arteriole vasoconstriction
sympathetic innervation and catecholamines from the adrenal medulla
110
what percentage of filtrate is reabsorbed in the PCT
65%
111
reabsorbed filtrate in the PCT is sent into
the peritubular capillaries
112
how is the movement of solutes and water osmosis driven in the PCT
cotransport and active transport of Na+
113
how much of resting ATP is necessary for filtrate reabsorption in the PCT
6%
114
what percentage of filtrate is reabsorbed in the nephron loop
25%
115
the filtrate reabsorbed in the nephron loop is sent into the
nephron loop
116
what molecules are reabsorbed in the DCT using hormone regulation
water, Na+, Cl-
117
filtrate reabsorbed in the DCT is sent into the
peritubular capillaries
118
at what part of the kidney is urine finished being produced
DCT
119
water conservation and urine concentration occurs in what part of the kidney
the collecting duct
120
purposes of tubular secretion
acid-base balance, waste removal, clearance of drugs and contaminents
121
H+ secretion in the renal tubule raises/lowers pH of blood
raises
122
HCO3 secretion raises/lowers pH of blood
lowers
123
waste removed through tubular secretion
nitrogenous waste and bile acid
124
tubular secretion occurs in
the renal tubule, mostly the DCT, but also the collecting duct
125
how does tubular secretion occur
active transport and diffusion
126
water conservation in the nephron loop
generates the high osmolarity and salinity of medulla ECF
127
Is the solute concentration in the nephron loop low/high
high
128
the deeper into the medulla, the higher/lower the salinity
higher
129
where does urine concentration occur
collecting duct
130
urine concentration in the collecting duct occurs through what process
osmosis of water
131
function of nephron loop
generates high salinity of medulla ECF
132
the nephron loop receives filtrate from
the PCT
133
descending limb is the thin/thick segment that ascends/descends into the medulla
thin, descends
134
the descending limb is permeable to water or salts
water
135
the ascending limb is the thin/thick segment that descends/ascends in the medulla
thick/ascends toward the cortex
136
the ascending limb is permeable to water/salts
salts
137
the ascending limbs delivers filtrate to
the DCT
138
the countercurrent multiplier multiplies
the medulla ECF salinity
139
how does fluid move in the countercurrent multiplier
fluid moves the opposite direction of the ascending/descending limbs
140
as fluid moves through the descending limb, there is an environment of
increasing osmolarity to cause water to leave filtrate
141
how much filtrate is concentrated at the bottom of the nephron loop
1200 mosm/L
142
in the ascending limb, more/less salt is pumped out of the ascending limb than water lost from the descending limb
more
143
is filtrate more or less dilute entering the DCT than leaving the PCT
more
144
vasa recta
capillaries of the medulla that reabsorb material from the nephron loop
145
does the vasa recta change the medulla osmolarity
no
146
the vasa recta reabsorbs equal/different amounts of water and alts
equal
147
diffusion of molecules from the descending capillaries of the vasa recta
mostly NaCl diffusing into blood and some water diffusing out
148
diffusion of molecules in ascending capillaries of the vasa recta
same NaCl diffuses out of the blood, mostly water diffuses in
149
more water reabsorption in the collecting duct causes
more concentrated urine and lower urine volume
149
after water conservation, how many more times can urine be concentrated
4x
150
renin-angiotensin aldosterone mechanism
hormonal system that regulated blood pressure in the kidney
151
the RAA mechanism is regulated by
the nephron reabsorption and GFR
152
when systemic BP falls, what happens to the hormones that act on the kidney
causes the juxtaglomerular cells to secret Renin
153
renin
hormone that converts angiotensinogen to angiotensin I
154
angiotensin converting enzyme converts
angiotensin I to angiotensin II
155
angiotensin II
potent vasoconstriction hormone that raises blood pressure
156
effects of angiotensin II at the renal corpuscle
constricts the efferent arterioles more than afferent arterioles
157
how does angiotensin II prevent a GFR drop
keeps glomerular Blood pressure high
158
the angiotensin II stimulates the adrenal cortex to secrete
aldosterone
159
aldosterone
hormone that causes Na+ reabsorption in the DCT
160
what in the blood does aldosterone raise
blood volume and blood pressure
161
antidiuretic hormone is produced by ________ and secreted by ______-
hypothalamus, posterior pituitary
162
function of the antidiuretic hormone
reduces urination and increase blood volume and pressure
163
antidiuretic hormone makes the collecting duct more/less permeable to water
more
164
antidiuretic hormone causes more/less water to be reabsorbed by the collecting duct
more
165
less water in urine means what about the characteristics of urine
lower volume, more concentrated
