CLINICAL MEDICINE

Detailed explanation-1: -The mean body content of sodium in the adult male is 92 g, half of which (46 g) is located in the ECF at a concentration of 135–145 mmol/L, ∼11 g is found in the intracellular fluid at the concentration of ∼10 mmol/L, and ∼35 g is found in the skeleton.

Detailed explanation-2: -Within the extracellular fluid, the major cation is sodium and the major anion is chloride. The major cation in the intracellular fluid is potassium. These electrolytes play an important role in maintaining homeostasis.

Detailed explanation-3: -When a neuron is at rest, sodium ions (Na+) are at a higher concentration outside the membrane in the extracellular fluid than in the intracellular fluid or cytoplasm.

Detailed explanation-4: -Total body sodium content Extracellular fluid contains 50% of the total body sodium; Intracellular fluid contains 5% of the total body sodium.