A plasma protein that maintains normal plasma osmotic pressure is \ \ \ \ \ \ ? - RUHS, Jaipur, PB B.Sc Nursing Entrance-2019

RUHS, Jaipur, PB B.Sc Nursing Entrance-2019

Applied Physiology

Easy

Appeared in: RUHS, Jaipur, PB B.Sc Nursing Entrance-2019

Explanation

Albumin is the most abundant protein in the plasma, making up about 55-65% of the total plasma proteins.
Due to its high concentration and relatively small molecular weight, albumin is responsible for 75-80% of the colloid osmotic pressure (oncotic pressure) of the plasma.
This osmotic pressure is essential for retaining fluid within the vascular compartment, preventing it from leaking into the interstitial spaces.
Albumin also serves as a major transport protein for various substances, including hormones, fatty acids, and drugs.

Option B: Thyroglobulin is not a primary plasma protein and its main function is not related to osmotic pressure.
Option C: Hemoglobin is not a plasma protein; it is contained within red blood cells.
Option D: While Transferrin is a plasma protein, its primary role is not maintaining osmotic pressure.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Function of Plasma Proteins as background academic context rather than a clinical decision trigger.
A nurse monitoring a patient with liver cirrhosis or nephrotic syndrome must be vigilant for signs of edema (e.g., pitting edema in the lower extremities, periorbital edema) and ascites, as these are direct consequences of hypoalbuminemia and decreased osmotic pressure.
When administering IV albumin, the nurse's primary assessment is to monitor for a decrease in edema and an increase in urine output, which indicates fluid is moving from the interstitial space back into the vascular system and being excreted by the kidneys.
What if? If a patient has severe burns, they lose large amounts of plasma and albumin through the damaged skin. This leads to a rapid drop in osmotic pressure and massive edema. The priority nursing intervention would be rapid fluid and albumin replacement to restore vascular volume and prevent hypovolemic shock.

How to Approach the Question

First, identify the key concepts in the question: 'plasma protein' and 'osmotic pressure'.
The question asks for the specific protein responsible for maintaining this pressure.
Recall the major proteins found in plasma and their primary functions.
Evaluate each option: Albumin (osmotic pressure, transport), Thyroglobulin (thyroid hormone precursor), Hemoglobin (oxygen transport, inside RBCs), Transferrin (iron transport).
Based on this functional recall, determine that albumin is the protein whose main role is to regulate plasma osmotic pressure.
Select the option corresponding to Albumin.

Concept Tested & Keywords

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