Which substances are listed as key molecular substances affecting fluid shifts?

Which substances are listed as key molecular substances affecting fluid shifts?

• A. Hydrogen, sodium, potassium, chloride, calcium, phosphorus, magnesium, proteins, O2, CO2, HCO3, and glucose.
• B. Cholesterol, triglycerides, and choline.
• C. Vitamin A, Vitamin D, and calcium.
• D. Hemoglobin, myoglobin, and ferritin.

Answer: (A)

Fluid shifts between body compartments are driven by osmotic and oncotic forces created by dissolved particles. The substances that most powerfully shape these gradients are electrolytes (such as sodium, potassium, chloride, calcium, magnesium, and phosphate), proteins that contribute to plasma oncotic pressure, and small solutes like glucose and bicarbonate that add to osmolarity. Hydrogen ions reflect acid-base balance, which also alters how fluids distribute. The collection that includes H+, Na+, K+, Cl−, Ca2+, phosphate, Mg2+, proteins, O2, CO2, HCO3−, and glucose captures the range of solutes that influence osmotic pressure and acid-base status, and thus fluid movement. The other groups involve lipids, vitamins, or oxygen-transport proteins that don’t directly drive the osmotic gradients governing fluid shifts.

Fluid shifts between body compartments are driven by osmotic and oncotic forces created by dissolved particles. The substances that most powerfully shape these gradients are electrolytes (such as sodium, potassium, chloride, calcium, magnesium, and phosphate), proteins that contribute to plasma oncotic pressure, and small solutes like glucose and bicarbonate that add to osmolarity. Hydrogen ions reflect acid-base balance, which also alters how fluids distribute.

The collection that includes H+, Na+, K+, Cl−, Ca2+, phosphate, Mg2+, proteins, O2, CO2, HCO3−, and glucose captures the range of solutes that influence osmotic pressure and acid-base status, and thus fluid movement. The other groups involve lipids, vitamins, or oxygen-transport proteins that don’t directly drive the osmotic gradients governing fluid shifts.