Which is the plasma proteins that constitutes about 40 to 60 % of total plasma proteins?

RRB Nsg. Superintendent-20 July 2019 (Shift-2)

Biochemistry & Nutrition

Easy

Appeared in: RRB Nsg. Superintendent-20 July 2019 (Shift-2)

Explanation

Albumin is the most abundant plasma protein, constituting approximately 55% to 60% of the total, which falls squarely within the 40-60% range mentioned in the question.
Its main function is to maintain colloid osmotic pressure (oncotic pressure), which is crucial for retaining fluid within the vascular system and preventing edema.
Albumin also acts as a significant transport protein for various substances, including hormones, free fatty acids, bilirubin, and certain drugs.

Option A: Fibrinogen makes up only about 4% to 7% of total plasma proteins, a concentration far below the 40-60% range.
Option B: Globulins account for approximately 35% to 38% of plasma proteins. While this is a significant amount, it falls just short of the 40-60% range specified.
Option D: Fibrin is an insoluble protein that is formed from fibrinogen during blood clotting. It is not a normally circulating protein in the plasma.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Composition and relative abundance of plasma proteins as background academic context rather than a clinical decision trigger.
Nurses monitor serum albumin levels as a key indicator of a patient's nutritional status, liver function, and kidney health. Low levels (hypoalbuminemia) can suggest malnutrition, liver cirrhosis, or nephrotic syndrome.
Hypoalbuminemia leads to decreased plasma oncotic pressure, causing fluid to shift from the blood vessels into the interstitial tissues, resulting in generalized edema. This is a critical assessment finding.
What if? If a patient has severe burns, they lose large quantities of albumin through the damaged skin. This leads to a rapid drop in oncotic pressure, causing massive fluid shifts (third-spacing), severe edema, and potentially life-threatening hypovolemic shock.

How to Approach the Question

First, identify the key detail in the question: the requirement for a plasma protein that constitutes '40 to 60%' of the total.
This is a factual recall question based on the fundamental composition of blood plasma.
Mentally review the major plasma proteins and their approximate concentrations. Recall that Albumin is the most abundant.
Compare the known percentages to the given range: Albumin (55-60%) fits perfectly. Globulins (38%) are below the range. Fibrinogen (~4-7%) is significantly lower.
Eliminate 'Fibrin' because it is the end product of coagulation, not a primary protein circulating in plasma.
Based on this comparison, select Albumin as the only option that matches the specified abundance.

Concept Tested & Keywords

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