Exam 4- Renal Flashcards
1
Q
How many nephrons does each kidney have?
A
1 million
2
Q
Gain: sources of H+ finding pH homeostasis (3 ways)
A
- generation of H+ from CO2 (resp)
- increase of H+ due to loss of HCO3- in diarrhea or other nongastric GI fluids (metabolic)
- increase of H+ due to loss of HCO3- in the urine
3
Q
Loss: sources of H+ finding pH homeostasis (3 ways)
A
- loss of H+ in vomitus (metabolic)
- loss of H+ in the urine (metabolic)
- hyperventilation (resp)
4
Q
acidosis due to processes other than respiration, low blood pH
A
metabolic acidosis
5
Q
- lactic acid build-up due to severe exercise
- diarrhea (this gets rid of bicarbonates- creating more acidic environment
A
examples of metabolic acidosis
6
Q
alkalosis due to processes other than respiration, rising blood pH
A
metabolic alkalosis
7
Q
- excessive vomiting
- intake of excess bases- antacids (tums)
A
examples of metabolic alkalosis
8
Q
- respiratory rate (HYPO)
- increase CO2
- increase H+
- decrease pH
- decrease bicarbonate
A
acidosis
9
Q
- respiratory rate (HYPER)
- decrease CO2
- decrease H+
- increase pH
- increase bicarbonate
A
alkalosis
10
Q
extracellular fluid should be at a pH of
A
7.4
11
Q
reversibly binding H+
A
buffering
12
Q
the major extracellular buffer is the ____ system
A
CO2/HCO3-
13
Q
normal range for pH of blood
A
7.35 - 7.45
14
Q
normal PCO2 is ___ mmHg
A
45 - 35
15
Q
normal HCO3 is ___ mEq/L
A
21 - 26
16
Q
function of kidneys: regulate
A
water (volume of blood/ dehydration), pH of extracellular fluid (blood plasma & interstitial fluid), inorganic ions
17
Q
functions of kidneys: remove
A
wastes and foreign chemicals from blood to excrete as urine
18
Q
functions of kidneys: produce
A
- erythropoietin (hormone)
- renin (enzyme)
- 1,25- dihydroxy vitamin D (hormone- calcium balance)
19
Q
- glomerular
- peritubular
A
2 sets of capillaries
20
Q
two sets of capillaries:
_____: filtration
A
glomerular
21
Q
two sets of capillaries:
____: reabsorption of filtrate to blood supply
A
peritubular
22
Q
- afferent
- efferent
A
two sets of arterioles
23
Q
where blood flows into glomerular capillaries
A
afferent
24
Q
where blood leaves the glomerulus
A
efferent
25
part of the renal tubule that lies close to the glomerulu
Proximal convoluted tubule (PCT)
26
part of the renal tubule that loops into the renal medulla
Loop of Henle
27
part of the renal tubule that is the most distant from the glomerulus
Distal convoluted tubule (DCT)
28
receives filtrate from several nephrons
Collecting duct
29
fluid entering the glomerular capsule
Filtrate
30
functional unit of the kidney
Nephron
31
transport urine from kidneys to bladder (peristalsis of smooth muscle help move urine)
ureters
32
store urine until voided from body
bladder
33
carry urine from bladder to the outside of the body
urethra
34
somatic motor neurons stimulate external urethral sphincter
Guarding reflex
35
somatic motor neurons inhibit external urethral sphincter
Voiding reflex
36
compound that increases urine output, leading to decreased water conservation
Diuretic
37
the bladder stores urine until it is excreted from the body by the ___
micturition reflex
38
Micturition is initiated by a _______ which causes the smooth muscle of the bladder walls (detrusor muscle) to contract and expel the urine
nervous reflex
39
Detrusor (smooth muscle):
- type: during filling
- parasympathetic (causes contraction): inhibited
internal urethral sphincter (smooth muscle):
- sympathetic (causes contraction): stimulated
external urethral sphincter (skeletal muscle):
- somatic motor (causes contraction): stimulated
gaurding reflex
40
Detrusor (smooth muscle):
- type: during micturition
- parasympathetic (causes contraction): stimulated
Internal urethral sphincter (smooth muscle):
- sympathetic (causes contraction): inhibited
External urethral sphincter (skeletal muscle):
- somatic motor (causes contraction): inhibited
voiding reflex
41
capillary to lumen
- A substance may enter tubules through glomerular filtration
secretion
42
passing of substances from the lumen (tubules) to the capillary
- substances may leave the tubule through this
reabsorption
43
waste (urine) on its way out of the body
excretion
44
reabsorption and secretion require a substance to move across a layer of ___
epithelial cells
45
reabsorption occurs constantly in ____ and ____ and is not subject to hormonal control
proximal and loop of henle tubules
46
___ and ___ tubules are subject to control reabsorption
distal and collecting tubules
47
products of reabsorbed at high rates:
- glucose + most organic nutrients
- water and many ions (Na+, K+)
48
for products like these, the kidneys just help in maintaining plasma levels of the nutrients
glucose + most organic nutrients
49
- kidneys can aid in regulating these
- ex: water intake decreases, kidneys water reabsorption increases
water and many ions (Na+, K+)
50
most reabsorption occurs in ____ 65%
proximal tubule
51
- active process
- occurs in all tubular segments except the descending limb
sodium reabsorption
52
- osmosis
- dependent upon sodium reabsorption
water reabsorption
53
Na+ and Cl- combine to form NaCl in the interstitial fluid which will drive the reabsorption of _____
water
54
Throughout tubule, Na+ is reabsorbed by _____
-Na-K+ ATPase pump
primary active transport
55
water follows ions as they move
passive process
56
coupling of water reabsorption to sodium reabsorption: what does this mean
- Na+ moves first
- interstitial increases in osmolality
- H2O moves to create an equilibrium
57
The descending loop of Henle is relatively _____to solutes and freely permeable to water
impermeable
58
the ascending limb is ___ to solutes, but not water
permeable
59
water is drawn out by osmosis due to the interstitial fluid is HYPERTONIC (water will move to the higher conc. of solutes)
descending loop
60
- Na+ move from the thick portion to the epithelial cells via electrochemical gradient, this drives the secondary active transport of Cl- and K+.
- K+ diffuses back into filtrate, Na is pumped into interstitial fluid, Cl- passively follows
ascending loop
61
-Due to close location and each loops affect on the surrounding interstitial fluid between the loops, a _____ is generated
positive feedback system
62
-end of the positive feedback
-determined by the active transport pumps
max concentration
63
countercurrent multiplier system sets up a _____ water reabsorption (into blood)
concentration favoring
64
Must ingest these substances to replace loss-kidneys will minimize excretion until you do so
Na+ and H2O
65
major nitrogenous waste product
-helps set up solute concentration gradients
urea
66
_____is triggered by increase in plasma osmolality and decrease in ECF
-stimulate vasopressing
thirst
67
_________= more aquaporings=more water retained=less water secreted
more vasopressin
68
location for highest water permeability (ie highest # of aquaporins)
proximal tubule
69
Permeability varies depending on location in tubule and presence of
aquaporins
70
large amounts of water in urine due to low vasopressin
water diuresis
71
vasopressin stimulates presence of ____ in the ___, without it permeability is low
Aquaporins; collecting ducts
72
after vasopressin locks in, ________ activates enzyme that causes proteins to increase rate of fusion of vesicles to membrane
secondary messenger
73
Na+ reabsorption is regulated by _____ once in the distal tubule
aldosterone
74
hormone stimulates _____ in distal convoluted tubule and cortical collecting ducts
Na+/K+ pumps
75
What ion is most abundant in cells?
K+
76
Where is K+ filtered?
glomerulus
77
Most reabsorption of K+ occurs where?
proximal and loop of henle
78
secretion of urea by facilitated diffusion
ascending limb
79
almost all urea filtered originally is present
-reabsorption happens again
-much of which is secretive back into ascending limb
distal tubule
80
what is secreted into the renal tubules?
H+, K+, organic anions move from the peritubular capillaries into the tubular lumen
81
Tubular secretion is an important mechanism for:
1. ___
2. ____
3. disposing of drugs and drug metabolites
1. excess K+
2. controlling blood pH (H+, HCO3-)
82
something from the renal tubules to the bloodstream
reabsorption
