1. Body Fluids

Question 1

Homeostasis

Answer 1

relative constancy of Milieu Intérieur

Question 2

Body water percentage (PRI)

Answer 2

60%

Question 3

Physiological Reference Individual (PRI)

Answer 3

21 yo white male 70kg

Question 4

Body water varies with

Answer 4

sex, age and body fat

Question 5

Body water of newborn

Answer 5

75%

Question 6

Body water after puberty

Answer 6

women = 50%
men = 60%

Question 7

Body water over 65yo

Answer 7

women = 45%
men = 50%

Question 8

Calculating absolute body water

Answer 8

(weight(kg) x body water(%))/100

Question 9

Water balance

Answer 9

input = output

Question 10

Water input

Answer 10

• oral fluid
• oral intake as food
• oxidative water from metabolism

Question 11

Water output

Answer 11

• breathing (lungs)
• passive evaporation (skin)
• urine (kidneys)
• stool
• facultative loss

Question 12

Obligatory loss

Answer 12

will always be lost no matter the input, can be insensible or sensible

Question 13

Insensible loss

Answer 13

can’t feel it: breathing + passive evaporation loss

Question 14

Sensible loss

Answer 14

aware: urine + stool

Question 15

Facultative loss

Answer 15

vary with intake but necessary to maintain balance

Question 16

Insensible perspiration key points

Answer 16

• pure water
• passive evaporation
• entire skin surface (no sweat glands needed)
• continuous and obligatory

Question 17

Sweating key points

Answer 17

• electrolyte solution
• active secretion
• involves sweat glands
• activated by heavy work/temp

Question 18

Negative water balance

Answer 18

water loss greater than water intake

Question 19

Causes of negative water balance (5)

Answer 19

1. reduced intake
2. excessive loss from gut
3. excessive sweating
4. excessive loss in expired air
5. excessive loss in urine

Question 20

Positive water balance (water intoxication)

Answer 20

water loss smaller than water intake

Question 21

Causes of positive water balance

Answer 21

1. excessive intake
2. renal system failure

Question 22

2 major body water compartments and distribution

Answer 22

Intracellular Fluid (ICF) = 2/3, 40%
Extracellular Fluid (ECF) = 1/3, 20%

Question 23

Components of Extracellular Fluid

Answer 23

• plasma = 5%
• Interstitial Fluid (ISF) = 15%
• lymph
• transcellular fluid

Question 24

Hematocrit (Ht)

Answer 24

percentage of blood volume occupied by red blood cells

Question 25

Hematocrit formula

Answer 25

erythrocyte column height/whole blood column height

Question 26

Hematocrit normal value

Answer 26

45%

Question 27

Plasma

Answer 27

fluid medium in which blood cells are suspended

Question 28

Interstitial Fluid (ISF)

Answer 28

fluid which percolates between individual cells

Question 29

Lymph

Answer 29

lymphatic vessels

Question 30

Transcellular fluid

Answer 30

aggregate of small fluid volumes secreted by epithelial cells that line in body cavities

Question 31

Out of 60% body water:
- 40% =
- 20% =
->15% =
-> 5% =

Answer 31

• 40% = ICF
• 20% = ECF
  ->15% = ISF
  -> 5% = Plasma

Question 32

Indicator Dilution Method

Answer 32

add known quantity of indicator and measure concentration in unit/volume of plasma

Question 33

Indicator Dilution Method: calculating total body water

Answer 33

indicator must be able to cross capillary wall + cell membrane

Question 34

Indicator Dilution Method: calculating ECF

Answer 34

indicator can’t cross cell membrane

Question 35

Indicator Dilution Method: calculating plasma

Answer 35

indicator can’t cross capillary wall

Question 36

Indicator Dilution Method: calculating ICF

Answer 36

ICF = total body water - ECF
–> need 2 indicators

Question 37

Indicator Dilution Method: calculating ISF

Answer 37

ISF = ECF - Plasma
–> need 2 indicators

Question 38

Viability of cells depends on… and requires…

Answer 38

• relative constancy of internal environment
• exchanges within internal and external environment