Question

Maximum amount of K+ ion is seen in which GI secretion?

• A. Saliva
• B. Colonic
• C. Gastric
• D. Jejunal

Hint:

Salivary ducts secrete K+ and reabsorb Na+, giving saliva a high potassium content.

Answer 1

The Correct Option is A

Step 1: Each gastrointestinal secretion has a characteristic electrolyte profile. The question asks which one has the highest concentration of potassium (K+).

Step 2: Saliva is the GI secretion richest in potassium. Salivary potassium concentration is markedly higher than that of plasma, because the salivary ducts reabsorb sodium and secrete potassium as the saliva passes through them.

Step 3: The other secretions have lower potassium content. Gastric, jejunal and colonic fluids contain potassium, but their concentrations are lower than that of saliva (colonic fluid is also potassium rich, yet saliva has the highest concentration among the options offered).

Step 4: Hence the maximum potassium content among these GI secretions is found in saliva, option a.