Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Human Physiology II > CH14+15 - Urinary System & Fluid/Acid Balance > Flashcards

CH14+15 - Urinary System & Fluid/Acid Balance Flashcards

1
Q

What are the functions of the kidney?

A

-important in maintaining homeostasis of the body
-filter waste material (180L/hour in blood)
-help regulate BP
-regulate water/ion/acid-base balance
-produce hormones (for BP/kidney regulation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How many kidneys do we have?

A

2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the urinary system parts?

A

-Kidney
-Ureter = between kidney and bladder, helps move material to bladder for storage
-Bladder
-Urethra (shorter in females — often end up with bladder infections b/c bacteria can go back up)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What’s in the urine is indicative of what?

A

-what’s in urine = what’s been processed in the kidney
-in morning pee = dark (because at night not drinking water)
-drink lots of water, pee = lighter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What exits the kidney?

A

urine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the functional unit of the kidney?

A

nephron (smallest piece of kidney)
-different lengths

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the two elements/components of the kidney?

A

-vascular components —> blood containing, wrap all around nephron
-tubular elements —> waste collecting elements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Go through the blood flow process (vascular components) of the kidney.

A

1) Afferent arteriole —> incoming blood into nephron
2) Glomerulus (blob of blood vessels)
3) Efferent arteriole —> blood leaving the glomerulus
4) Peritubular capillaries —> wrap all around the waste tubules, so blood and waste can interact (for filtration, but also reabsorption to bring material back — otherwise the blood vessels shrivel up)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Go through the waste collecting process (tubules/tubular elements) of the kidney.

A

1) Bowman’s capsule —> “container” that wraps around the Glomerulus (materials squeeze out of blood and go into capsule)
2) Proximal tubule —> near Bowman’s capsule —twists around, convoluted (things wrap around each other)
3) Loop of Henle —> deep loop that comes down and comes back up (for reabsorption), short or long depending on nephron size
4) Distal Tubule —> near the end of nephron — DCT (distal convoluted tubule), still fine-tuning things, no urine yet
5) Collecting Duct —> several nephrons go into one, can still fine-tune/bring waste in

once urine = all waste

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the area with the Glomerulus and Bowman’s capsule called?

A

renal corpuscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the 4 processes that happen in the kidney?

A

1) Filtration —> material coming out = filtrate
-filtration barriers (some stuff will go through if its through holes, some will not)
-can’t choose what goes through, just depends on size of holes (NON-specific)
-ONLY in renal corpuscle
2) Reabsorption —> material taken from tubules, back into blood
-everywhere EXCEPT renal corpuscle
3) Secretion —> material from blood into waste collecting tubules
-more specific, body recognizes material and wants it out
-everywhere EXCEPT Loop of Henle
-ACTIVE process
4) Excretion —> urine leaves collecting duct, into the ureter, into the bladder, and then the urethra

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Filtration only happens in the…?

A

renal corpuscle (Glomerulus —> Bowman’s capsule)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Loop of Henle is only for…?

A

reabsorption (of NaCl and H2O)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is in the filtrate?

A

-only smaller things can go through (water, ions — Na+, K+, glucose, urea)
-proteins, RBCS = TOO BIG, can’t get through

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What surrounds/wraps all around the Glomerulus?

A

podocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where do podocytes originate from?

A

Bowman’s capsule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How do podocytes wrap around the Glomerulus capillaries?

A

-foot processes (pedicels) that extend from the podocytes wrap around the blood vessels
-form layer between blood and waste

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the 3 filtration barriers?

A

1) Capillary pores —> spaces between endothelial cells of blood vessel (allows some small things through these spaces)

2) Basement membrane (capillaries’ extracellular matrix of proteins/carbs that forms a meshwork) —> has some spaces in between that stuff can go through if it fits
-net negative charge (prevents things of like charge from going through — like proteins)

3) Filtration slit —> created by spaces in between the podocyte foot processes (some things can go through the spaces)

-material has to go through ALL 3 barriers, thus filtrate usually just water + ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is hydrostatic pressure (in general)?

A

the pressure that builds up when you fill any container (ex. get too full, the more it resists filling)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the 3 pressures that work in the kidney?

A

1) glomerular hydrostatic pressure
2) glomerular oncotic/colloid osmotic pressure
3) bowman’s capsule hydrostatic pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Explain glomerular hydrostatic pressure and how it affects filtration.

A

-as blood flows into the glomerulus, resist filling (increases pressure)
-creates squeezing out effect (PUSHING pressure — forces material from blood through filtration barriers into Bowman’s capsule)
-works WITH filtration (driving force of filtration)
-naturally varies — the higher your BP, the higher your glomerular hydrostatic pressure (more blood flows in)
-usually 55-60 mmHg (strongest of the pressures)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Explain glomerular oncotic pressure and how it affects filtration.

A

-PULLING of water back into glomerulus (going down its concentration gradient [high]—>[low])
-in the blood: less water, more proteins (like cholesterol) — cannot get across barriers = stuck in the blood
-in the filtrate (Bowman’s capsule): more water, little to no protein
-thus water goes back into blood/glomerulus
-works AGAINST filtration
-usually around ~30 mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Explain Bowman’s capsule hydrostatic pressure and how it affects filtration.

A

-as Bowman’s capsule gets more filled up, pressure builds up, resists filling up and PUSHES backwards (doesn’t vary a lot)
-works AGAINST filtration
-weakest, usually around ~15 mm Hg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is GFR?

A

glomerular filtration rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the net filtration pressure (NFP)?

A

-all 3 pressures put together —> give an idea of how filtration will proceed
-usually 10-15 mmHg (60-30-15)
-pathology can change these numbers:
1) high [protein] in blood = higher oncotic pressure = LOWER NFP
2) low BP = low glomerular hydrostatic pressure = LOWER NFP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Is filtration an active process?

A

NO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Is secretion an active process?

A

YES (requires energy)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Loop of Henle is specifically for…?

A

-reabsorption of NaCl and H2O
-important, so we don’t get dehydrated (LONGER Loop of Henle in desert animals — have less water, need lots of room to absorb more water)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are the 2 mechanisms for regulation of filtration (to make sure filtration is happening at the right rate, not too fast/slow)?
Can they come in conflict?

A

1) local: intrinsic/autoregulation —> controlling GFR, kidneys regulate themselves
2) systemic: extrinsic regulation —> control of BP (body most concerned with potential dehydration + BP)
-in body, outside kidney — but kidney also involved

-both involve tubuloglomerular feedback (interaction between blood and waste) in the juxtaglomerular apparatus

-YES, can come in conflict (kidney & body) —> ex. dehydrated body will tell kidney to NOT filtrate, but kidney wants to

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are juxtaglomerular/granular cells?

A

-part of the lining of Afferent arteriole
-modified smooth muscle cells (constrict/dilate)
-detect flow coming out of afferent arteriole (too fast/too slow?) —> sit on either side of blood coming into glomerulus and monitor speed
-secrete renin (hormone that regulates BP in the entire body)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are macula densa cells?

A

-line Loop of Henle’s ascending limb
-detect NaCl in waste tubule (indirect detection of flow rate by monitoring NaCl —> ex. if Na+ is coming by too quickly)
-know how much material is in the tubules by looking at NaCl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the detectors and what are the responders from granular cells and macula densa cells?

A

-macula densa cells = DETECTORS
-granular cells = RESPONDERS
1) secrete renin
2) constrict (less can get through) / dilate (more can get through)

33
Q

What is the purpose of the TAL part of the Loop of Henle?

A

twists around close to Afferent arteriole —> super close, thus allows for communication (of macula densa cells and granular cells)

34
Q

Explain the local mechanism (intrinsic/autoregulation) of filtration regulation.

A

1) GFR falls —> less flow detected by macula densa through LOW NaCl
2) triggers granular cells to dilate (dilation of Afferent arteriole)
3) LESS resistance = more blood flow in = GFR can go back up

35
Q

Explain the systemic mechanism (extrinsic) of filtration regulation.

A

driven by BP:
1) BP falls = glomerular hydrostatic pressure falls
2) thus, GFR falls —> detected by macula densa cells (low NaCl)
3) triggers granular cells to secrete renin to tend to whole body
4) angiotensin II allows for vasoconstriction of Efferent arteriole
-MORE resistance = more constriction
5) blood coming into glomerulus has a harder time leaving = increase in glomerular hydrostatic pressure = increase in BP

36
Q

What is myogenic regulation?

A

-involves ONLY granular cells —> modified smooth muscle of afferent arteriole
-main idea: increased flow to stretch receptors on smooth muscle cells = trigger constriction = reduce GFR to normal (and vice versa)

37
Q

How does amount of fluid in body affect BP?

A

amount of fluid in body directly influences BP (ex. LESS fluid = LOW BP)

38
Q

How does Na+ and H2O play a part indirectly in impacting BP?

A

if you reabsorb Na+, water will follow as an osmotic effect (impacts BP)
-ex. less reabsorption of Na+ = less water reabsorption (dehydration) = LOW BP

39
Q

Low fluid = LOW systemic BP —> The systemic response will override kidneys to maintain BP. Why?

A

-don’t want BP to get too low (can’t transport blood efficiently, especially to brain)
-shut down kidneys to prevent water loss via filtration

40
Q

Where does most reabsorption occur?

A

proximal tubule (active and passive)
-almost all (water, ions, etc.) reabsorbed immediately after filtration

41
Q

What is considered the distal nephron?

A

distal tubule & collecting duct
-end of nephron, most of work already done —> can be used to help regulate water or acid/base balance
-depends on what body needs (ex. if dehydrated, will reabsorb water)

42
Q

Urine volume = __% total filtrate volume.

A

1%
-most of the filtrate is taken back, very small amount ends up in urine
-depends on body state (need more/less water)

43
Q

Is reabsorption an active process?

A

YES
-requires energy to set up sodium gradient (then passive transport/reabsorption will use this gradient)
-sodium driven reabsorption —> worth investing ATP to set up sodium gradient to absorb other materials like glucose, water, etc.

44
Q

Filtration removes about __% of blood, but reabsorption means that only about __% will actually leave the kidney.

A

-20%
-1%

45
Q

Walk through the steps of reabsorption in the proximal tubule.

A

reabsorption = tubule to blood
1) lumen/filtrate (in proximal tubule) to cell (that line the tubule)
2) across cell (crossing over of membranes) to interstitial fluid (fluid that surrounds cells)
3) through interstitial fluid to blood (peritubular capillary)

46
Q

What materials get reabsorbed and in what order?

A

1) Reabsorb Na+ (positive ions)
2) Reabsorb water (leaves tubules by osmosis — follows Na+)
3) Reabsorb negative ions

47
Q

Walk through the reabsorption of sodium in the proximal tubule and how energy is required for this.

A

1) PASSIVE: sodium (from lumen/filtrate just after Bowman’s capsule) into tubular cell
-NO energy needed b/c of [sodium] gradient — [outside cell] > [inside cell]
-only have this gradient b/c the Na+/K+ ATPase pump constantly pumps Na+ outside cell

2) sodium across the cell to other side

3) ACTIVE: moving sodium OUT of cell (into interstitial fluid) — need energy b/c against concentration gradient ([low] —> [high])
-K+ transported INTO cell
and gets secreted (ends up in tubule)
-Na+ into interstitial fluid
-drives sodium gradient which then drives all the other gradients (all other reabsorptions — ex. water follows, helps regulate BP)

4) sodium into peritubular capillary (blood)
-interstitial fluid and peritubular capillary have about the same ion makeup, thus Na+ diffuses

48
Q

What is aldosterone?

A

-hormone made in adrenal glands (close proximity to kidneys)
-helps with sodium reabsorption (BEYOND proximal — in distal tubule mainly)
-works as a transcription factor (interacts with nucleus directly — “build me more proteins”) to make more transporters (not clear which ones)
-therefore, can upregulate reabsorption of Na+ (in distal tubule mainly — ex. more sodium transporters = more sodium)
-part of the RAAS (renin-aldosterone-angiotensin system)

49
Q

What does RAAS stand for, and what is its main purpose?

A

-renin aldosterone angiotensin system
-main purpose is to maintain BP (therefore systemic, mostly works outside kidney)

50
Q

What are signals to activate the RAAS pathway?

A

-low NaCl
-low ECF (extracellular fluid) volume
-low arterial BP

51
Q

How does angiotensinogen get activated to its active form (angiotensin II)?

A

angiotensinogen = inactive, circulating in blood, waiting for RAAS pathway to be activated
1) renin (released from granular cells when low BP) hormone also an enzyme, activates it to angiotensin I
2) ACE (angiotensin converting enzyme — made in lungs, into pulmonary circulation) quickly converts it to angiotensin II

52
Q

Walk through the responses of angiotensin II upon activation.

A

angiotensin II = “most important” — many responses, mainly increases BP
1) arteriolar vasoconstriction
-constrict all the blood vessels (narrower) = forces BP to go up

2) signals adrenal gland to produce aldosterone
-increase in Na+ reabsorption = increase in water reabsorption (and other ions) = increase in BP
-increase in K+ secretion (decrease in [K+])

3) increases fluid intake (increases thirst)
-more fluid in body = increase in BP

4) increases vasopressin/ADH production
-antidiuretic hormone — suppresses release of fluid (makes you pee less) by increasing water reabsorption = increase in BP

53
Q

If you’re really dehydrated (less water = more [NaCl]), what happens to aldosterone production?

A

BLOCK aldosterone b/c it increases sodium reabsorption, but don’t want more (severely dehydrated)
-other angiotensin II effects will still happen

54
Q

How does someone with hypertension avoid the RAAS pathway?

A

take ACE inhibitor drugs so there is NOT an increase in BP (angiotensin II never made)

55
Q

A person gets __% of water back in the proximal tubule/Loop of Henle.

A

80% (NOT variable)
-more variable water reabsorption at distal tubule/collecting duct

56
Q

What is an aquaporin?

A

-water pore
-don’t always have them, but helpful when we want to reabsorb more water (helps move water faster)
-usually found in later parts of nephron when we’re fine-tuning

57
Q

Why is water reabsorption largely passive?

A

increase in solutes draws more water — water follows Na+ (osmotic gradient, therefore not directly using energy)

58
Q

What is diabetes?

A

-cells can’t take up glucose = high blood glucose
-heavier glucose load in blood (more glucose than that can be reabsorbed)

59
Q

What is common testing for diabetes?

A

see if there is glucose in urine

60
Q

If filtration and reabsorption rates of glucose are equal…?

A

-NOT diabetic
-normal, NOT peeing out glucose
-the more you filter out, the more you reabsorb

61
Q

If at tubular maximum (TM) and above, what does that indicate?

A

TM = maximum glucose you can move (have specific carrier proteins)
-can only get so much glucose to be reabsorbed, maxed out, can’t reabsorb any faster = glucose in urine
-DIABETIC

62
Q

What does it indicate when below/above renal threshold?

A

-below: filtered, but not excreted (don’t pee out)
-above: filtered and excreted

63
Q

An example of secretion (taking things out of blood into waste tubules)?

A

K+
-interstital fluid => tubular cell => lumen
-requires energy [low in IF] —> [high in cell]

64
Q

Normal blood pH is ___. Anything ≥ ___ is alkalosis, and anything ≤ ____ is acidosis.

A

-normal pH ~7.4
-alkalosis ≥ 7.5
-acidosis ≤ 7.3
(fairly minor fluctuations mess up balance)

65
Q

What is an effect of acidosis/alkalosis?

A

proteins/enzymes start to breakdown — unfunctional, no longer at optimal pH

66
Q

Which is more common from acidosis/alkalosis?

A

acidosis
-a lot of materials going into body acidic (metabolism, change in breathing — hypoventilation = high [CO2])

67
Q

What are the 3 ways to maintain acid-base balance?

A

1) chemical buffers
-HCO3- (create a lot when transporting CO2)
-PO₄³⁻ — phosphate

2) respiratory mechanisms
-change in breathing (hypo/hyper ventilation)
-only used to fix acid/base imbalance NOT due to breathing/respiratory disorder

3) renal mechanisms
-acidosis: kidneys secrete protons (H+) to get in less acidic state
-alkalosis: reabsorb/make new HCO3-

-if any of these stop working, the others can compensate (make up for it)

68
Q

What main process/equation is involved in acid-base balance?

A

CO2 + H2O <—> H+ + HCO3-
-carbonic anhydrase (conversion of CO2 into proton and bicarbonate)

69
Q

What is compensation?

A

-body’s attempt to correct the problem by altering some other part of the process (full compensation takes several days)
-fixing the problem: pH = normal, BUT other things abnormal (i.e., CO2/HCO3-/H2O levels)
-example: metabolic acidosis —> respiratory mechanisms fix this so well (change breathing depth b/c want to get rid of protons), breathe out so much CO2 that you “overshoot/overcompensate”

70
Q

If acid-base imbalance is uncompensated/partially compensated/fully compensated, what is affected?

A

1) uncompensated: pH is abnormal
-PCO2 OR HCO3- abnormal

2) partially compensated: pH is close to normal
-BOTH PCO2 and HCO3- abnormal

3) fully compensated: pH is normal
-BOTH PCO2 and HCO3- abnormal

71
Q

Respiratory acidosis:

A

-origin: high CO2
-drives equation to RIGHT (causing high H+ and HCO3-)

72
Q

Respiratory alkalosis:

A

-origin: low CO2
-drives equation to LEFT
(causing low H+ and HCO3-)

73
Q

Metabolic acidosis:

A

-origin: high H+
-drives equation to LEFT (causing low HCO3- as it binds to H+ to get rid of it)

74
Q

Metabolic alkalosis:

A

-origin: low H+
-drives equation to RIGHT
(causing an increase in HCO3-)

75
Q

Fluid volume and solute concentration move in _____ (same/opposite) directions.

A

opposite

76
Q

PCO2 of 6 mm Hg and a blood pH of 7.1. What is the underlying acid-base disorder?

A

metabolic acidosis
-pH < 7.4 = acidosis
-PCO2 doesn’t make sense (if respiratory would be high) = metabolic

77
Q

pH = 7.55 and PCO2 = 52 mm Hg. What is the underlying acid-base disorder?

A

metabolic alkalosis
-pH > 7.4 = alkalosis
-PCO2 doesn’t make sense (if respiratory would be low) = metabolic

78
Q

A student has normal PCO2 levels, high H+ levels, low pH, and low HCO3- levels in the blood. What is the underlying acid-base disorder?

A

metabolic acidosis
-pH < 7.4 = acidosis
-H+ and HCO3- opposite = metabolic
-pH and CO2 also don’t match (don’t show same trend) = metabolic

Human Physiology II (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions