Fluid, Electrolyte, and Acid-Base Homeostasis

Question 1

Explain the danger of water intoxication

Answer 1

provokes disturbances in electrolyte balance, resulting in a rapid decrease in serum sodium concentration and eventual death.

Question 2

Define electrolyte and give four functions for the ions

Answer 2

ions form when electrolytes dissolve and
dissociate

Control osmosis of water between body fluid
compartments

Help maintain the acid-base balance (HCO3-, H+, OH-)

Carry electrical current (Na+, K+,Ca2+)

Serve as cofactors (Ca2+, Mg2+)

Question 3

Describe how the body regulates the balance of the following ions:
sodium

Answer 3

 Most abundant ion in ECF (90% cations)

 Plays pivotal role in fluid and electrolyte balance
because it account for almost half of the
osmolarity of ECF

Question 4

Describe how the body regulates the balance of the following ions:
Chloride Cl

Answer 4

 Most prevalent anions in ECF

 Moves relatively easily between ECF and ICF
because most plasma membranes contain Cl-
leakage channels and antiporters

Question 5

Describe how the body regulates the balance of the following ions:
Potassium K+

Answer 5

 Most abundant cations in ICF

 Key role in establishing resting membrane
potential in neurons and muscle fibers

 Also helps maintain normal ICF fluid volume

 Helps regulate pH of body fluids when exchanged
for H+

Question 6

Explain why the removal of excess hydrogen ions from the body is so important

Answer 6

The overabundance of hydrogen ions makes the blood excessively acidic and then, the hydrogen ions are moved out by the proximal convoluted tubules and collecting tubules (both are nephrons of the kidneys) via the secretion process, thus making the urine more acidic and blood less acidic

Question 7

Explain how the carbonic acid-bicarbonate buffer system helps regulate the pH of body fluids.

Answer 7

In this system, gaseous metabolic waste carbon dioxide reacts with water to form carbonic acid, which quickly dissociates into a hydrogen ion and bicarbonate

Question 8

acidosis

Answer 8

a condition in which there is too much acid in the body fluids

leads to depression of CNS causing comas

Question 9

alkalosis

Answer 9

a condition in which there is too much base in the body fluids

can lead to an excitability of the CNS causing seizures.