Fluids & Electrolytes Balance

Question 1

What are the functions of body water?

Answer 1

Act as a lubricant,
Solvent for electrolytes
Medium for transport of solutes
Required for cellular metabolism
Digestion & Elimination
Maintains body temperature

Question 2

What does the total percentage of water depend on?

Answer 2

Age and gender

Question 3

What is the average percentage water in males and females?

Answer 3

Males = 60%
Females = 55%

Question 4

What causes the difference in percentage between individuals?

Answer 4

Amount of adipose tissue

Question 5

What is the water content in :
Plasma
Skin
Skeleton
Adipose tissue

Answer 5

Plasma: 90%
Skin: 70 to 80%
Skeleton: 22%
Adipose: 10%

Question 6

Why is water in urine and alveoli not considered part of total body water volume?

Answer 6

It is from an external environment

Question 7

What is intracellular fluid?

Answer 7

Blood cells’ water volume and water within other cells too

Question 8

What is extracellular fluid?

Answer 8

Water present outside of cells or circulatory system

Question 9

What does extracellular fluid divide into?

Answer 9

Plasma and Interstitial fluid

Question 10

What is plasma?

Answer 10

Water outside of the cells but within the circulatory system.

Question 11

What is interstitial fluid?

Answer 11

Water volume between cells

Question 12

What percentage does intracellular volume take up?

Answer 12

2/3 of all body fluids (~67%)

Question 13

Where is the extracellular fluid contained?

Answer 13

In the extracellular compartment

Question 14

What is transcellular fluid?

Answer 14

Special type of ECF that is grouped with interstitial fluid

Question 15

What does the transcellular fluid include?

Answer 15

Lymph, CSF, synovial fluid, aqueous humor, vitreous body, endolymph, perilymph, pleural, pericardial and peritoneal fluid

Question 16

What is osmosis?

Answer 16

The movement of water between interstitial and intracellular fluid

Question 17

What is the water between plasma and interstitial fluid occurred by?

Answer 17

Filtration, reabsorption

Question 18

What are filtration and reabsorption governed by?

Answer 18

Capillary blood pressure and colloid osmotic pressure

Question 19

What happens if you add hypotonic NaCl to an isotonic solution?

Answer 19

Decreased osmolarity,
Increased ICF and ECF
Cells swell

Question 20

What happens if you add hypertonic NaCl to an isotonic solution?

Answer 20

Increase in osmolarity
Decrease in ICF and increase in ECF
Cells will decrease in size

Question 21

What is the normal osmolarity of NaCl?

Answer 21

0.9%

Question 22

What does acute hyponatremia lead to?

Answer 22

Brain edema

Question 23

What does chronic hyponatremia lead to?

Answer 23

Na+, Cl- and K+ are transported from ICF to ECF, accumulates osmotic flow of water into cells and swelling of tissue

Question 24

What are the three main mechanisms with which substances enter and leave the capillaries?

Answer 24

Diffusion
Transcytosis
Bulk flow (filtration and reabsorption)

Question 25

What is the most important method of capillary exchange?

Answer 25

Simple diffusion

Question 26

What happens during simple diffusion?

Answer 26

Oxygen and nutrients move from blood to interstitial fluid
Carbon dioxide and wastes move from interstitial fluid to blood

Question 27

Why can’t most plasma proteins and red blood cells pass through to capillaries?

Answer 27

Due to their size, too large

Question 28

What is transcytosis?

Answer 28

When substances within blood plasma enter endothelial cells through endocytosis, move across and exit the cell through exocytosis.

Question 29

How do substances enter the endothelial cells during endocytosis of transcytosis?

Answer 29

Within tiny pinocytotic vesicles

Question 30

What kind of substances is transcytosis important for?

Answer 30

Large, lipid-insoluble molecules, such as insulin and antibodies

Question 31

What is bulk flow?

Answer 31

Large numbers of ions, molecules or particles in fluid moving together in the same direction

Question 32

What direction does bulk flow happen in?

Answer 32

From area of high concentration to area of lower

Question 33

What is filtration?

Answer 33

Pressure driven movement of fluid and solutes from blood capillaries into interstitial fluid

Question 34

What is reabsorption?

Answer 34

Pressure-driven movement of fluid and solutes from interstitial fluid into blood capillaries

Question 35

Why is bulk flow important?

Answer 35

Regulation of relative volumes of blood and interstitial fluid.

Question 36

How is water exchange between plasma and interstitial fluid determined?

Answer 36

Balance between hydrostatic pressures and colloid osmotic pressures ( Starling equilibrium)

Question 37

What are the four pressures in Starling’s equilibrium?

Answer 37

Blood Colloid Osmotic Pressure (towards capillary)
Interstitial Fluid Hydrostatic Pressure (towards capillary)
Blood Hydrostatic Pressure (away from capillary)
Interstitial Fluid Osmotic Pressure (away from cAPILLARY)

Question 38

What is the equation for net flow balance?

Answer 38

(BHP + IFOP) - (BCOP + IFHP)

Question 39

Which pressures promote filtration?

Answer 39

BHP and IFOP

Question 40

Which pressure promote reabsorption?

Answer 40

BCOP and IFHP

Question 41

What volume of water is taken in and lost everyday?

Answer 41

2.5 liters

Question 42

How is water gained?

Answer 42

Ingestions of liquids and moist food (2.2 to 2.3l)
Metabolic synthesis (0.2 to 0.3l)

Question 43

How is water lost?

Answer 43

Insensible water loss through skin by evaporation ( 0.6l) and by exhalation (0.3l)

Feces (0.1l)

Urine (1.5l)

Question 44

What is the osmolarity through-out the body?

Answer 44

Osmolarity is identical in all fluid compartments