Body fluid compartments (intra and extracellular fluids)

Question 1

Most important means by which body maintains a balance between intake and output is by ……..

Answer 1

controlling the rates at which the kidneys excrete these substances.

Question 2

plasma and interstitial (extracellular) composition

Answer 2

Highly permeable capillary membrane
Protein level > in plasma because of low membrane permeability

Na+, Cl- and HCO3-

Question 3

Intracellular fluid composition

Answer 3

Separated by cell membrane
Highly permeable to water not electrolytes (semi-permeable)

K+, Mg+, proteins, and PO4+

Question 4

Gibbs Donnan Equilibrium

Answer 4

2 solutions containing ions are separated by membrane that is permeable to some of the ions but not to others –> electrochemical equilibrium is established

Question 5

The principle of conservation of mass:

Answer 5

total mass of a substance after dispersion in the fluid compartment will be the same as the total mass injected into the compartment.

Question 6

Distribution of fluid between intracellular & extracellular compartments determined by……

Answer 6

osmotic effect of small solutes.

Question 7

Electrolytes or small ions (i.e.: sodium & chloride) determine distribution of…..

Answer 7

fluids across the semi-permeable cell membrane

Question 8

______ ______ cause fluids to shift between compartments

Answer 8

Osmotic factors

Question 9

Rate of diffusion of water is called _____.

Answer 9

Osmosis

Question 10

_______ refers to the # of particles in solution rather than molar concentration

Answer 10

Osmole

Question 12

1 mole of NaCl –> dissolve into solvent (1 L) –> Concentration of ……

Answer 12

2 osm/L solution (Na <—> Cl)

Question 13

Osmolality:

Answer 13

Osmoles / kg of water

Question 14

Osmolarity

Answer 14

Osmoles / liter of solution

Question 15

_______ _______ refers to the amount of pressure required to prevent osmosis.

Pressure applied in ______ direction of osmosis

Answer 15

osmotic pressure
opposite

Question 16

Osmotic pressure of a solution is ________ to the concentration of osmotically active particles

Answer 16

proportional

Question 17

1 mOsm gradient change = ________ mmHg. osmotic pressure

Answer 17

19.3mmHg

Question 18

Interstitial Fluid & Plasma: _____% due to ____ and ____ ions.

Answer 18

80% due to sodium and chloride

Question 19

Intracellular Fluid: ____% due to ______ ions

Answer 19

50% due to potassium

Question 20

Total osmolarity of each compartment:

Answer 20

300 mOsm/L

Question 21

Conditions of HYPONATREMIA:

Answer 21

Diarrhea & Vomiting
Diuretic abuse
Addison’s Disease
Excess water retention (ADH)

Question 22

Conditions of HYPERNATREMIA:

Answer 22

Lack of ADH
Diabetes insipidus
Dehydration
Aldosterone secretion

Question 23

If plasma sodium concentration rapidly falls below ____ to _____ mmol/L, brain swelling may lead to seizures, coma, permanent brain damage, and death.

Answer 23

115 to 120 mmol/L

Question 24

Because the skull is rigid, the brain cannot increase its volume by more than about ___percent without it being forced down the neck(herniation),which can lead to permanent brain injury and death.

Answer 24

10

Question 25

Primary loss of water from the extracellular fluid results in_______ and _______/

Answer 25

hypernatremia and dehydration
DI

Question 26

Excessive secretion of the sodium-retaining hormone ________can cause a mild degree of hypernatremia and overhydration.

Answer 26

aldosterone

Question 27

Intracellular edema can occur in certain conditions:

Answer 27

Inflammation has a direct effect on increasing cell membrane permeability
Depression of cellular metabolic function
Lack of nutrition to the cells
Decreased blood flow: reduced oxygen & nutrient supply
Ionic pumps of cell membrane require oxidative metabolism (ATP) to remove intracellular sodium

Question 28

Two general causes of extracellular edema:

Answer 28

1. Abnormal leakage from plasma
2. Lymphatic failure to return fluids to blood

Question 29

Abnormal leakage from plasma: (3)

Answer 29

Excessive capillary filtration rate
Filtration dependant on permeability & surface area of capillary
Starling factors: hydrostatic pressure & colloid osmotic pressure

Question 30

Abnormal leakage from plasma: 3 Causes

Answer 30

Increased capillary filtration coefficient

Increased capillary hydrostatic pressure

Decreased plasma colloid osmotic pressure

Question 31

Lymphatic failure to return fluids to blood: (3)

Answer 31

Lymphatic blockage preventing return of proteins to plasma
Increased interstitial colloid osmotic pressure
Cancer, surgery, infection (filaria nematodes)

Question 32

Causes of Extracellular Edema:

Answer 32

1. Increased capillary pressure
2. Decreased plasma protein
3. Increased capillary permeability
4. Blockage of lymph return

Question 33

Edema caused by HF:
_____ _____ to the kidneys is reduced and this reduced blood flow stimulates secretion of_____, causing increased formation of _______ and increased secretion of ________ both of which cause additional salt and water retention by the kidneys.

Answer 33

Blood flow
Renin
angiotensin II
aldosterone

Question 34

Safety Factors That Prevent Edema:

Answer 34

1. The safety factor caused by low tissue compliance in the negative pressure range is about 3 mm Hg.
2. The safety factor caused by increased lymph flow is about 7 mm Hg.
3. Wash down” of interstitial fluid proteins (as lymphatic flow increases proteins are washed away)

Question 35

Renal Blood flow =

Answer 35

22% of cardiac output (1100ml/min

Question 36

Renal blood flow in order =

Answer 36

Renal artery —-> segmental arteries —-> interlobar arteries —–> arcuate arteries interlobular arteries —-> afferent arterioles ——> glomerular capillaries

“RSI AIA”

Question 37

Highest metabolism is in the Renal ______.

Answer 37

Cortex

Question 38

Describe Cortical Nephrons:

Answer 38

Short loops of Henle, extend to outer medulla
Outnumber juxtamedullary nephrons ~7:1

Question 39

Describe Juxtamedullary Nephrons:

Answer 39

Extend deep into medulla with long loops of Henle
Play a big role in concentrating urine
Just a few, deeper and into medulla