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BIOS
BIOS256/ BIOS 256 E XAM 3: (NEW 2025/ 2026
UPDATE) ANATOMY AND PHYSIOLOGY IV REVIEW| QS & AS|
GRADE A| 100% CORRECT (VERIFIED ANSWERS)
1. What is the most abundant component of body fluid?:
Water
2. What percentage of body fluid is water?: 45%-60%
3. What percentage of water are newborns?: 75%
4. What are the major fluid components of the body?:
Intracellular (ICF) and Extracellular (ECF)
5. What percentage of fluid is ICF?: 65%
6. What percentage of fluid is ECF?: 35%
7. What components make up the ECF?: 25% interstitial fluid,
8% blood plasma and lymph, and 2% transcellular fluid
8. Intracellular fluid: found inside the cells and makes up the
majority of all body fluids
BIOS256
, 9. Extracellular fluid: found outside of the cells and can be
divided into interstitial fluid (80%) and blood plasma (20%)
10. What are the general function of electrolytes?: Controls
osmosis of water, regulate bodily secretions, maintains acid-
base balance, carries the electric currents for graded and
action potentials, and serves as cofactors for enzymatic
activities 11. What is natriuresis?: Increased excretion of
sodium by the kidneys, caused by natriuretic peptides, which
inhibits sodium and water reabsorption, therefor the kidneys
secrete more sodium and water which lowers the blood
pressure
12. What hormone promotes natriuresis?: ANP
13. If sodium is high outside the cell what happens to
potassium?: Potassium is high in the cell, they are always
opposite.
14. What is the most abundant cation in the ECF?: Sodium
15. What is the most abundant anion in the ECF?: Chloride
16. What is the most abundant cation in the ICF?: Potassium
BIOS
BIOS256/ BIOS 256 E XAM 3: (NEW 2025/ 2026
UPDATE) ANATOMY AND PHYSIOLOGY IV REVIEW| QS & AS|
GRADE A| 100% CORRECT (VERIFIED ANSWERS)
1. What is the most abundant component of body fluid?:
Water
2. What percentage of body fluid is water?: 45%-60%
3. What percentage of water are newborns?: 75%
4. What are the major fluid components of the body?:
Intracellular (ICF) and Extracellular (ECF)
5. What percentage of fluid is ICF?: 65%
6. What percentage of fluid is ECF?: 35%
7. What components make up the ECF?: 25% interstitial fluid,
8% blood plasma and lymph, and 2% transcellular fluid
8. Intracellular fluid: found inside the cells and makes up the
majority of all body fluids
BIOS256
, 9. Extracellular fluid: found outside of the cells and can be
divided into interstitial fluid (80%) and blood plasma (20%)
10. What are the general function of electrolytes?: Controls
osmosis of water, regulate bodily secretions, maintains acid-
base balance, carries the electric currents for graded and
action potentials, and serves as cofactors for enzymatic
activities 11. What is natriuresis?: Increased excretion of
sodium by the kidneys, caused by natriuretic peptides, which
inhibits sodium and water reabsorption, therefor the kidneys
secrete more sodium and water which lowers the blood
pressure
12. What hormone promotes natriuresis?: ANP
13. If sodium is high outside the cell what happens to
potassium?: Potassium is high in the cell, they are always
opposite.
14. What is the most abundant cation in the ECF?: Sodium
15. What is the most abundant anion in the ECF?: Chloride
16. What is the most abundant cation in the ICF?: Potassium
