The Body Fluid Compartments

Question 1

Insensible water loss

Answer 1

Water loss that we are not consciously aware of

Question 2

Sources by which water is added to the body

Answer 2

1. Ingested in the form of liquid or water in food

2. Synthesized in the body by oxidation of Carbohydrates

Question 3

Amount of water ingested

Answer 3

2100ml/day

Question 4

Water intake through metabolism

Answer 4

200ml/day

Question 5

Total amount of daily intake of water

Answer 5

2300ml/day

Question 6

How is water lost by the body

Answer 6

1. Insensible water loss
2. Fluid loss in sweat
3. Water loss in feces
4. Water loss by the kidneys

Question 7

Ways in which water is lost through Insensible water loss

Answer 7

1. Evaporation from respiratory tract

2. Diffusion through the skin

Question 8

Amount of water lost through Insensible water loss

Answer 8

700ml/day

Question 9

Amount of water lost through Evaporation from respiratory tract

Answer 9

300-400ml/day, during prolonged heavy exercise 650 ml/day

Question 10

Amount of water lost by diffusion through the skin

Answer 10

300-400ml/day

Question 11

How is diffusion through skin minimized

Answer 11

Cholesterol filled cornified layer of skin

Question 12

How is water lost through respiratory tract

Answer 12

Air enters the respiratory and becomes saturated with moisture to a vapor pressure of 47mmHg before it is expelled. Because the inspired air is below 47mmHg water is continuously lost through respiration.

Question 13

Why do we get a dry feeling in the respiratory passage during cold weather

Answer 13

Air inspired has a vapor pressure that decreases to nearly 0 causing a great loss of water through the lungs as the temperature decreases

Question 14

Amount of water lost through sweat

Answer 14

100ml/day, in hot weather or heavy exercise increases to almost 1-2L/hour (5000ml/day)

Question 15

How is water lost through sweat over come

Answer 15

Activation of the thirst mechanism

Question 16

Amount of water loss through feces

Answer 16

100ml/day, sometimes increases to liters per day in people with severe diarrhea

Question 17

Amount of water lost by kidneys

Answer 17

1400ml/day, during prolonged heavy exercise 500ml/day

Question 18

Total body fluid distributed between two compartments

Answer 18

Extracellular and intracellular fluids

Question 19

Types of extracellular fluid

Answer 19

1. Interstitial fluids
2. Blood plasma
3. Transcellular fluid

Question 20

Transcellular fluids

Answer 20

Fluids in enclosed compartments like :fluid in Synovial, peritoneal, pericardial, intra ocular s spaces and cerebrospinal fluid. Specialized fluid and some cases its composition is much different from plasma or Interstitial fluids

Question 21

Amount of Transcellular fluid present in the body

Answer 21

12L

Question 22

Total body water of a 70kg adult man

Answer 22

Body water is about 60% of the body weight /about 42L.

Question 23

Percentage of body water depends on

Answer 23

Agree, gender, and degree of obesity.

Question 24

As person grows older body fluid decreases

Answer 24

Aging is associated with an increased percentage of body weight being fat which decreases the percentage of water in the body

Question 25

Women body water percentage

Answer 25

Did to greater percentage of body fat their total body water averages about 50%

Question 26

Premature and new born babies total body water

Answer 26

70-75%

Question 27

Amount of intracellular fluid

Answer 27

28L that is about 40%of total body weight

Question 28

Amount of extracellular fluid

Answer 28

Makes up 20%of the Body weight that is 14L in 70kg man

Question 29

Amount of Interstitial fluid

Answer 29

11L

Question 30

Amount of plasma in the body

Answer 30

1/4th of extracellular fluid 3L

Question 31

Average volume of blood

Answer 31

7%of body weight about 5L. 60% plasma and 40% red blood cells

Question 32

Hematocrit

Answer 32

Fraction of blood composed of red blood cells determined by centrifuging blood in a "Hematocrit tube" until the cells Brecon tightly packed in the bottom of the tube. 3-4%plasma remains entrapped among the cells therefore true Hematocrit is only 96%of the measured Hematocrit

Question 33

Plasma and Interstitial fluid separated by

Answer 33

Capillaries membrane

Question 34

Plasma have higher concentration of_____ than in Interstitial fluid

Answer 34

Protein because of low permeability of capillaries to plasma Proteins

Question 35

Donnan effect

Answer 35

Plasma protein have have a net negative charge therefore binds to positively charged ions (cation) and since are in greater conc in the plasma give the plasma a higher conc of positively charged ions. Conversely - vely charged Proteins repel - vely charged ions (anions) therefore having a higher conc. In the Interstitial fluid.

Question 36

Ion content of extracellular fluid

Answer 36

Large amount of Sodium, Chloride, bicarbonate ions and small amounts of calcium, potassium, magnesium, phosphate and organic acid ions

Question 37

Ionic content of intracellular fluid

Answer 37

Large amounts of potassium, phosphate, magnesium, sulfate ions and proteins and small amount of Sodium, Chloride ions and almost no calcium

Question 38

Indicator-dilution method

Answer 38

It's a method of measuring volume of fluid compartments. Indicator sub is placed in the compartment allowing it to disperse evenly throughout them a sample is taken out and analyzed. It uses the conservation of mass principle. If no sub leaks out total mass of the sub of sub in compartment will be equal to total mass of sub injected

Question 39

What is needed to be know for calculation using indicator-dilution method

Answer 39

1. Total amount of sub infected | 2. Concentration of fluid in chamber after sub is dispersed

Question 40

Formula of the indicator - dilution method

Answer 40

Vol B= Vol A x conc A /conc B

Question 41

Indicator- dilution method used only when

Answer 41

1. Dispersed evenly 2. Disperse only in the compartment to be measured 3. Indicator is not metabolized or excreted before reaching equilibrium 4. Indicator easily and accurately measured 5. Indicator is non toxic

Question 42

Measurement of total body water

Answer 42

Use of radioactive water(tritium), heavy water (dueterium) or antipyrine (lipid soluble easily penetrate membrane)

Question 43

Measurement of extracellular fluid

Answer 43

Subs that are not readily permeable through cell membrane. Radioactive Sodium, radioactive chloride, radioactive iothalamate, thiosulfate ions and insulin. Sometimes radioactive Sodium diffuse into the cells in small amounts therefore measurement is not true

Question 44

Calculation of intracellular volume

Answer 44

Measured Indirectly | IC vol= total body water - EC Vol

Question 45

Measurement of plasma volume

Answer 45

Subs that do not readily penetrate capillaries membrane. Serum albumin labeled with radioactive iodine, dyes that bind to plasma Proteins like Evans Blue dye (T-1824)

Question 46

Calculation of Interstitial fluid

Answer 46

IF vol= EC Vol - plasma volume

Question 47

Measurement of blood volume

Answer 47

Total blood vol = plasma vol / 1-hematocrit or inject RBCs labeled with radioactive material like radioactive chromium and calculated using indicator-dilution method