Block 8

Question 1

What all is included in “total water loss” (including all methods of elimination)

Answer 1

Urination - 1200mL

Evaporation at skin (insensible) - 750mL

Evaporation at lungs (insensible) - 400mL

Lost in feces - 150mL

total = ~2500mL

Question 2

What parameters are associated with metabolic alkalosis?

Answer 2

pH > 7.45

high blood pH (low [H+]) and high HCO₃^-

primary causes are prolonged vomiting and thiazide diuretic use

Question 3

Filtration fraction = ________

Answer 3

GFR / Renal Plasma Flow

(RPF = renal blood flow x (1 - hematocrit))

So, the filtration fraction is the fraction of renal plasma flow that is filtered (and it’s about 20% so 0.2)

Question 4

What is the importance of H+ concentration regulation?

Answer 4

regulation is essential because activities of almost all enzyme systems in the body are influenced by the hydrogen ion concentration

Question 5

List what happens when the osmoreceptor-ADH mechanism is activated.

Answer 5

• water deficit/increased extracellular osmolarity is detected by the osmoreceptors
• increased ADH secretion by posterior pituitary
• plasma ADH levels increase
• water permeability at DCT and collecting ducts increases
• water reabsorption increases/excretion decreases
• osmolarity goes back down

Question 6

What is the most concentrated urine can be? What conditions are required to make it that concentrated?

Answer 6

1200-1400 mOsm/L

The basic requirements are:

• high renal medullary interstital fluid osmolarity (if the osmolarity is too low, water will not want to move into the interstitial space)
• High level of ADH (increases the permeability to water, allowing it to be reabsorbed more easily in the DCT and collecting ducts)

Question 7

GFR stands for _______ and it is equal to about ______ of the renal plasma blood flow.

How is it determined?

Answer 7

Glomerular filtration rate

20%

determined by:

• balance of hydrostatic and colloid osmotic forces acting on the capillary membrane
• capillary filtration coefficient (K_f), which is the product of the permeability and filtering surface area of capillaries

Question 8

Identify the site of action and function of atrial natriuretic peptide.

Answer 8

site of action - distal tubule/collecting duct

Decreases NaCl reabsorption

Question 9

Describe the composition of glomerular filtrate.

Answer 9

Because glomerular capillaries are impermeable to proteins, they are essentially protein free and devoid of cellular elements (like RBCs)

• otherwise, the filtrate is similar to regular plasma in terms of concentrations of most other small molecules and salts (however, small molecular weight sbustances such as calcium and fatty acids are not free filtered as they are partially protein bound)

Question 10

Describe what occurs in the distal tubules.

Answer 10

The first portion has the juxtaglomerular complex, which provides feedback control for GFR and blood flow.

The next portion is referred to as the diluting segment because it functions similarly to the thick ascending limb of the loop (it also dilutes tubule fluid and 5% of the filtered load of NaCl is reabsorbed).

The filtered Na is then pumped out of the cells by Na/K ATPase, Cl diffuses into the interstitial space via Cl channels, and the solutes are then picked up by the peritubular capillaries.

Question 11

Renal clearance is defined as…

and it is determined by…

Answer 11

the volume of plasma that is completely cleared of a substance by the kidneys per unit time.

It’s determined by the concentration of a substance found in urine multiplied by the urine flow rate divided by the plasma concentration of the substance

(C_s = U_s x V / P_s)

Question 12

Urinary excretion = …

Answer 12

glomerular filtration - tubular reabsorption + tubular secretion

Question 13

Describe what occurs in the LATE distal tubules and the collecting ducts.

Answer 13

The principle cells reabsorb sodium and water from the lumen as well as secrete potassium ions into the lumen.

Aldosterone antagonists will compete with aldosterone for binding sites here. (the normal effect of aldosterone is to enhance the secretion of potassium and reabsorption of sodium)

The intercalated cells reabsorb potassium ions and secrete hydrogen ions into the tubular lumen (hydrogen is secreted by hydrogen ATPase).

Question 14

What safety factors normally prevent edema?

Answer 14

• low compliance of the interstitium when the interstitial fluid pressure is in the negative pressure range
• ability of lymph flow to increase 10-50 fold
• washdown of interstitial fluid protein concentration, which reduces interstitial fluid colloid osmotic pressure as capillary filtration increases

Question 15

________ is the situation where (as a result of loss of negative charge from the basement membrane) lower molecular weight proteins like albumin are filtered and appear in urine

Answer 15

Proteinuria or albuminuria

Question 16

Amiloride and triamterene are ___________, so they inhibit…

Answer 16

sodium channel blockers, so they inhibit the sodium reabsorption and potassium secretion in collecting tubules

Question 17

Identify the site of action and function of PTH.

Answer 17

site of action - proximal tubules (decreases phosphate ion reabsorption)

site of action (2) - thick ascending loop of Henle/distal tubules (increases calcium reabsorption)

Question 18

The two factors that influence the glomerular capillary colloid osmotic pressure are:

Answer 18

1 - arterial plasma colloid pressure (if it the arterial increases, then the capillary increases; this, in turn, decreases GFR)

2 - the fraction of plasma filtered by the glomerular capillaries (increases in the filtration fraction will concentrate and raise the glomerular capillary colloid osmotic pressure, which in turn reduces GFR)

Question 19

the coordinated functions of the ______, ______, and ______ create an acid-base balance.

Answer 19

Liver

Kidneys

Lungs

Question 20

What is the actual countercurrent multiplier?

Answer 20

The repetitive reabsorption of sodium chloride by the asending loop of Henle and the continued inflow of new sodium chloride by the PCT into the loop of Henle

Question 21

Glomerular hydrostatic pressure is determined by 3 variables. What are they and how do changes in them affect GHP?

Answer 21

1 - arterial pressure: increased arterial pressure –> increase (this effect is buffered by autoregulatory mechanisms that maintain a relatively constant glomerular pressure as BP fluctuates)

2 - afferent arteriolar resistance: increased resistance –> decrease (more resistance would mean less blood flow, which decreases GFR and hydrostatic pressure)

3 - efferent arteriolar resistance: increased resistance –> increased pressure (only to a point; constriction increases the resistance to outflow, which raises pressure, but if the increase gets too high then you’ll get decreased blood flow, increased filtration fraction, and increased glomerular capillary colloid osmotic pressure and decreased GFR)

Question 22

Why is precise control of potassium concentration necessary?

Answer 22

Because many cell functions are sensitive to fluctuations in potassium ECF concentration.

Question 23

Factors that stimulate secretion of potassium are…

Answer 23

• increased ECF concentration of potassium
• increased aldosterone (also stimulates sodium/water reabsorption)
• increased distal tubular flow rate

Question 24

The primary cause of hypocapnia (low blood pCO2) is…

Answer 24

hyperventilation

Question 25

Describe the purpose of respiratory compensation.

Answer 25

- changes in the respiratory rate helps to stabilize the pH of ECF when CO2 levels increase, pH falls (so the addition of CO2 drives the buffer system to the right, and breathing rate needs to increase) when CO2 levels fall, pH rises (so removal of CO2 drives the buffer system to the left, and breathing rate slows)

Question 26

What are the two components to tubuloglomerular feedback and how does it work?

Answer 26

Afferent and Efferent Arteriolar Feedback The complex consists of macula densa cells in the initial portion of the DCT and juxtaglomerular cells in the walls of the arterioles. The macula densa sense changes in volume delivery to the DCT. - decreased NaCl causes dilation of afferent arterioles & increased renin release - increased GFR --\> increased flow --\> the macula dense signal to decrease GFR

Question 27

Glomerular hydrostatic pressure and capillary colloid osmotic pressure are the 2 determinants to GFR that are most variable and subject to physiological control. What are they influenced by?

Answer 27

1 - **sympathetic NS** (strong activation can constrict renal arterioles, decrease RBF, and decrease GFR; important for severe acute disturbances) 2 - **hormones** (**_NE and E both constrict_** afferent and efferent arterioles causing reductions in GFR and RBF; **_endothelin is a vasoconstrictor (decreased GFR)_**); **_angiotensin 2 preferentially constricts efferent_** vessels not afferent vessels, so this will actually ***_raise GFR_***; **_NO decreases resistance_** and would **increase GFR and excretion**; **PGE₂ and PGI₂ are vasodilators; bradykinin is a vasodilator**)

Question 28

Describe how renal compensation affects pH.

Answer 28

The rate of H+ and HCO₃^- secretion or reabsorption by the kidneys changes in response to changes in plasma pH (occurs in virtually all parts of the tubules except the loop of Henle) - buffers in urine are required to eliminate large numbers of H+ (carbonic-bicarbonate buffer system, phosphate buffer system, and ammonia buff system (which is mainly in the pct))

Question 29

the most important area for control of potassium secretion is

Answer 29

the distal tubule and cortical collecting duct

Question 30

Describe **_hyper_**natremia, including causitive factors and resulting symptoms.

Answer 30

Increased plasma sodium concentration, which also increases osmolarity, due to either loss of water from the ECF (concentrating the sodium) or excess sodium in the ECF Primary loss of water results in hypernatremia and dehydration. Possible causes: inability to secrete ADH; certain kidney result in loss of response to ADH

Question 31

Extracellular fluid edema occurs when... What are the 2 general causes?

Answer 31

occurs when excess fluid accumulates in the extracellular space general causes: 1 - abnormal leakage of fluid from the plasma to the interstitial space 2 - failure of the lymphatics to return fluid from the interstitial space to the blood (lymphedema)

Question 32

Describe what occurs in the Loop of Henle (descending and ascending)

Answer 32

**_Descending_**: reabsorbs more water (20%) due to an increase in medullary osmolarity (it's at this point that the tubular fluid is concentrated). The descending segment is highly permeable to water and moderately permeable to most solutes, including urea and sodium. **_Ascending_**: both the thin and thick portions are virtually impermeable to water; the thick portion active reabsorbs sodium, potassium, and chloride (25% of the filtered load) via the **NKCC2 transporters**. Tubular fluid dilutes here.

Question 33

Why do glomerular capillaries have a higher rate of filtration than other capillaries?

Answer 33

High glomerular hydrostatic pressure and a large K_f

Question 34

List some factors that can lead to extracellular edema.

Answer 34

- increased capillary pressure - decreased plasma proteins (decreased oncotic pressure) - increased capillary permeability - blockage of lymph return

Question 35

What are the components of the urinary system?

Answer 35

2 kidneys Urinary tract (ureters, urinary bladder, urethra)

Question 36

Define "insensible water loss".

Answer 36

Continous loss of water by evaporation from the respiratory tract and diffusion through the skin. We are not consiously aware of it (it is independent of sweating).

Question 37

Identify the MOA, site of action, and example of loops diuretics.

Answer 37

Ex. Furosemide and Bumetanide inhibit NKCC2 co-transport in luminal membrane Site of action: thick ascneding loop of Henle

Question 38

How do the intracellular and interstital fluid concentrations in males and females differ?

Answer 38

Males - 33% intracellular fluid and 21.5% interstitial fluid Females - 27% intracellular fluid and 18% interstitial fluid

Question 39

\_\_\_\_\_\_\_\_\_\_ and __________ are mineralocorticoid receptor antagonists that compete with aldosterone for receptor binding sites in the \_\_\_\_\_\_\_\_\_\_\_\_\_\_. What is the effect of their binding (as opposed to aldosterone binding)?

Answer 39

Spironolactone and eplerenone cortical collecting tubule They decrease reabsorption of sodium and secretion of potassium they're referred to as potassium sparing diuretics

Question 40

Describe what occurs in the proximal convoluted tubule.

Answer 40

the proximal tubules reabsorb 66% of the sodium and water (that is in the filtrate) it also reabsorbs the bicarbonate and glucose it has a high capacity for reabsorption due to its extensive brush border on the luminal side and the extensive labyrinth of intracellular and basal channels

Question 41

List and describe the majors layors found in glomerular capillary membranes.

Answer 41

1 - **_endothelium_**: perforated by thousands of small holes called fenestrae; protein cannot pass through (negatively charged) 2 - **_basement membrane_**: consists of meshwork of collagen & proteoglyacan fibrillae with large spaces (water and small solutes can filter); prevents proteins from filtering (again, due to the (-) charge) 3 - **_epithelial cells (podocytes)_**: surround the outer surface of the basement; are not continuous; have long "footlike" processes that encircle the outer surface; they're separated by "slit pores" through which filtrate moves

Question 42

Why does plasma have a higher cation concentration than interstitial fluid?

Answer 42

Higher presence of proteins (which are negative) so the cations tend to stick to them.

Question 43

Identify the site of action and function of ADH (vasopressin)

Answer 43

Site of action - distal tubule/collecting duct Increases water reabsorption

Question 44

What parameters are associated with respiratory acidosis?

Answer 44

pH \< 7.35 pCO2 \> 45 the respiratory system cannot eliminate all CO2 generated by the peripheral tissues

Question 45

Identify the site of action and function of aldosterone.

Answer 45

Site of action: distal tubule/collecting duct (on the principle cells) Increases NaCl and water reabsorption Increases K+ secretion

Question 46

What is (quantitatively) the most important buffering system?

Answer 46

The carbonic acid-bicarbonate system

Question 47

Blood is about \_\_\_% plasma and \_\_\_% RBCs. Hematocrit is the fraction of blood made of \_\_\_\_\_\_. What is the average hematocrit in men? In women?

Answer 47

60% plasma 40% RBCs Hematocrit is the fraction that's RBC's Men - 0.4 Women - 0.36 \*\*note, when measuring hematocrit it's impossible to completely pack the RBCs together in centrifuge so true hematocrit is only about 96% of the measured hematocrit because 3-4% of the plasma remains trapped among the cells

Question 48

Urea is a _________ that contributes about \_\_\_\_% to the osmolarity of the renal medullary interstitium when the kidney is forming maximally concentrated urine. What is the purpose of recirculating urea?

Answer 48

metabolic waste product 40% the recirculation of urea helps to trap it in the renal medullary area and contributes to the hyperosmolarity of the renal medulla.

Question 49

How does ADH function to control urine concentration?

Answer 49

If there is an increase in the osmolarity of normal body fluids, then the posterior pituitary will secrete ADH (vasopressin). This leads to increased permeability of the DCT and collecting ducts to water (aquaporins). Large amounts of water will be reabsorbed, thus decreasing the urine volume and osmolarity body fluids (the secretion of solutes does not change in response to ADH)

Question 50

Identify the MOA, site of action, and example of carbonic anhydrase inhibitors.

Answer 50

Acetazolamide inhibits the secretion of H⁺ and reabsorption of HCO₃^-, which decreases sodium reabsorption Site of action: proximal tubules

Question 51

Total body fluid is distributed mainly between which two compartments? What does each compartment consist of?

Answer 51

ECF (constitutes about 20% of total body weight and 14 liters of the average 42 liters in an average male): includes interstital fluid (3/4), plasma (1/4) and (sometimes) "transcellular fluid" (fluid in the synovial, peritoneal, and intraocular spaces, as well as the cerebrospinal fluid) ICF (about 28 of the 42 (on average) liters and 40% of total weight in an average male): includes the water inside cells \*\*Blood volume is both ECF and ICF because it includes plasma and RBC fluid

Question 52

What defenses does the body have to resist changes in pH?

Answer 52

1 - chemical acid-base buffer systems of body fluids 2 - respiratory center (lungs); reguluates the removal of CO2 (and therefore H2CO3) from extracellular fluid) 3 - kidneys; can excrete acidic or alkaline urine, thereby readjusting the extracellular fluid twoard normal (this is the most powerful)

Question 53

What is the primary means of physiological regulation of GFR?

Answer 53

Changes in glomerular capillary hydrostatic pressure (increases in hydrostatic pressure increase GFR and decreases in hydrostatic pressure decrease GFR)

Question 54

Explain the countercurrent multiplier mechanism. What is the result of this system?

Answer 54

Countercurrent multiplier mechanism: ## Footnote 1 - more salt is continually added to the interstitial fluid by the PCT; 2 - the higher the osmolarity of the ECF (interstitial fluid), the more water will leave the descending loop by osmosis; 3 - the more water that leaves the descending loop, the saltier the fluid is that remains in the tubule (higher osmolarity); 4 - the saltier the fluid, the more salt the ascending loop and tubule (DCT) is going to pump into the ECF; 5 - the more salt that is pumped out, the saltier the ECF is in the renal medulla (etc.) Result: the renal medullary interstitium is hyperosmotic

Question 55

True or false: changes in renal blood flow can influence GFR independently of changes in glomerular hydrostatic pressure

Answer 55

True

Question 56

The early distal tubule works to dilute urine by...

Answer 56

Reabsorbing sodium and chloride ions.

Question 57

What occurs in teh medullary collecting duct?

Answer 57

It draws water and urea out due to the hypertonicity of hte interstitium (due to sodium and bicarbonate). \< 10% of the filtered water and sodium is reabsorbed here (permeability is controlled by ADH) it can also secrete H+ to help with acid/base control

Question 58

What happens once substances have been absorbed across the tubular epithelial cells into the interstitial fluid?

Answer 58

They are transported through the peritubular carpillary walls into the blood by ultrafiltration (**bulk flow**) that is mediated by hydrostatic and colloid osmotic forces

Question 59

Renal oxygen consumption varies in proportion to \_\_\_\_\_\_\_\_, which in turn is related to GFR and the rate of sodium filtered. Why?

Answer 59

Renal tubular sodium reabsorption. If renal blood flow and GFR are reduced and less sodium is filtered, then less sodium is reabsorbed and less oxygen is consumed.

Question 60

Most of the calcium reabsorption takes place through ________ transport in the \_\_\_\_\_\_\_\_\_\_\_. (\_\_\_%) An additional \_\_\_\_\_% is reabsorbed __________ and ____________ at the ____________ limb of the loop of Henle. The remaining calcium that is reabsorbed is absorbed in the ______________ and it is done 100% through _______ transport.

Answer 60

Most of the calcium reabsorption takes place through **paracellular** transport in the **proximal convoluted tubules**. (**65**%) An additional **25-30**% is reabsorbed **paracellularly** and **transcellularly** at the **thick ascending** limb of the loop of Henle. The remaining calcium that is reabsorbed is absorbed in the **distal convoluted tubule** and it is done 100% through **active** transport.

Question 61

Identify the site of action and function of angiotensin 2.

Answer 61

Site of action: proximal tubule Increases NaCl and water reabsorption Increases H+ excretion

Question 62

What parameters are associated with metabolic acidosis?

Answer 62

Low blood pH (high [H+]) and low HCO3 pH \< 7.35 primary causes are severe diarrhea or ketoacidosis

Question 63

Identify the initial response of filtration to increased RBF. And after?

Answer 63

Increased blood flow will initially cause a decreased filtration fraction. When this happens, it slows the increase in glomerular capillary colloid osmotic pressure. This causes an increase in GFR.

Question 64

The most important regulators of calcium excretion by the GIT are

Answer 64

the kidneys and PTH

Question 65

What is the MOA of acetazolamide?

Answer 65

Inhibits the enzyme carbonic anhydrase in the proximal tubule (it's a carbonic anhydrase inhibitor), so it prevens the production of H+ and HCO₃^- from the decomposition of H₂CO₃. Thus, it also reduces sodium reabsorption (sodium is brought in in exchange for hydrogen ions)

Question 66

By which mechanism are sodium, chloride, and potassium reabsorbed from the thick ascending limb of the loop of Henle?

Answer 66

the NKCC2 transporter

Question 67

What are the different ranges for blood pH levels?

Answer 67

6-7 (death) 7-7.35 (acidosis) 7. 35-7.45 (normal) 7. 45-7.8 (alkalosis) 7. 8-9 (death)

Question 68

Identify the MOA, site of action, and example of aldosterone antagonists.

Answer 68

Spironolactone and eplerenone. inhibit aldosterone at its receptor, decreasing sodium reabsorption and decreasing potassium secretion Site of action: collecting tubules

Question 69

The filtration barrier refers to

Answer 69

the 3 layers of cells (podocytes, endothelial cells, and basemement membrane) that are responsible for filtration in the glomerulus

Question 70

Define the roles of ADH

Answer 70

- increases water resabsorption via aquaporin water channels in the DCT and collecting ducts - during water deprivation, increased plasma ADH increases reabsorption - during water excess, decreased plasma ADH reduces water reabsorption

Question 71

What are the two special features of renal medullary blood flow that contribute to the preservatino of the high solute concentration?

Answer 71

- medullary blood flow is low (1-2% of all renal blood flow) - the vasa recta serves as a countercurrent exchanger

Question 72

Outline the basics of the process of filtrate formation.

Answer 72

1 - fluid enters the renal corpuscle (containing the glomerulus, glomerular capsule, and capsular space) via afferent arteriole & exit via the efferent arteriole 2 - the fluid is filtered and about 20% of RBF enters the PCT (there will be variable reabsorption and secretion in the PCT) 3 - filtrate will travel through the loop of Henle (this includes water reabsorption in descending loop & solute reabsorption/secretion in ascending loop) 4 - finally, the filtrate enters the DCT (where small amounts of solutes and water may be reabsorbed here as well before exiting in the collecting ducts)

Question 73

# Fill in the following osmolarities: Initial glomerular filtrate: \_\_\_\_\_\_\_\_\_\_\_ Proxmial tubule: \_\_\_\_\_\_\_\_\_\_\_\_ Descending Loop: \_\_\_\_\_\_\_\_\_\_\_\_ Ascending Loop: \_\_\_\_\_\_\_\_\_\_\_\_ Distal tubule, cortical & medullary collecting ducts (in absence of ADH): \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

Answer 73

Initial glomerular filtrate: ~300 mOsm/L Proxmial tubule: little change Descending Loop: 600 mOsm/L Ascending Loop: 400 mOsm/L Distal tubule, cortical & medullary collecting ducts (in absence of ADH): 50 mOsm/L

Question 74

`Identify the MOA, site of action, and example of osmotic diuretics.

Answer 74

Ex. mannitol inhibit water and solute reabsorption by increasing osmolarity of tubular fluid site of action: mainly proximal tubules

Question 75

Identify the missing percentages of each substance in the human body. \_\_\_% water \_\_\_ % protein \_\_\_% fat \_\_\_% minerals \_\_\_% carbohydrates

Answer 75

65% water 16% protein 16% fat 4% minerals 1% carbohydrates

Question 76

pH is ______ related to [H+]

Answer 76

inversely

Question 77

\_\_\_\_\_ stimulates reabsorption of calcium in the DCT and cortical collecting duct, as well as activates vitamin D

Answer 77

parathyroid hormone

Question 78

What is the primary cause of hypercapnia (high blood pCO2)?

Answer 78

hypoventilation

Question 79

Define micturation.

Answer 79

The process by which the urinary bladder empties when it becomes filled.

Question 80

How can insulin clearance be used to estimate GFR?

Answer 80

Insulin is freely filtered (as freely as water) and not reabsorbed or secreted by the renal tubules (thus, filtration = clearance) The rate at which insulin is secreted is equal to the rate that it is filtered by the kidneys.

Question 81

Differential distribution of solutes is controlled by the work of the \_\_\_\_\_\_\_\_

Answer 81

Na/K ATPase

Question 82

The most important means by which the body maintains a balance between intake and output (as well as balance of electrolytes) is by...

Answer 82

controlling the rates at which the kidneys excrete these substances

Question 83

Identify the MOA, site of action, and example of thiazide diuretics.

Answer 83

Ex. Chlorthalidone, hydrochlorothiazide inhibit Na and Cl co-transport across the luminal membrane Site of action: early distal tubules

Question 84

Explain why the osmolarity of filtrate changes as it does throughout the course of the filtration process.

Answer 84

After running through the **proximal tubule**, there's little change because both water and solutes get reabsorbed (~66% of sodium along with some phosphate and other ions) The **descending loop** concentrates the filtrate because water is pretty much the only thing reabsorbed here. The **ascending loop** dilutes the filtrate because some reabsorption of sodium takes place here. After the **DCT and collecting ducts**, the osmolarity decreases again due to the reabsorption of Na and Cl

Question 85

Describe hyponatremia, including causitive factors and resulting symptoms.

Answer 85

Decreased plasma sodium concentration can result from loss of NaCl from ECF or excess water to ECF Conditions that cause hyponatremia include diarrhea, vomiting, and overuse of diuretics (prevent kidney from conserving sodium) Consequence of hyponatremia = cell swelling (low concentration of sodium implies high concentration of water)

Question 86

What parameters are associated with respiratory alkalosis?

Answer 86

respiratory system cannot generate enough CO2 pH \> 7.45 pCO2 \< 35

Question 87

Hydrostatic pressure inside the _________ promotes filtration, while hydrostatic pressure in the __________ opposes filtration. Colloid osmotic pressure of the _________ opposes filtration while colloid osmotic pressure of the _________ promotes filtration.

Answer 87

Hydrostatic pressure inside the **_capillaries_** promotes filtration, while hydrostatic pressure in the **_capsule_** opposes filtration. Colloid osmotic pressure of the **_capillaries_** opposes filtration while colloid osmotic pressure of the **_capsule_** promotes filtration.

Question 88

Which conditions are especially prone to causing intracellular swelling?

Answer 88

- hyponatremia - depression of metabolic systems of the tissues - lack of adequate nutrients to the cells