The plasma protein called antibodies are:

Appeared in: NVS- 2025

Explanation

Antibodies are specialized proteins produced by plasma cells (differentiated B lymphocytes) as a key component of the humoral immune system.
Chemically, antibodies are classified as immunoglobulins (Igs).
During serum protein electrophoresis, a laboratory technique used to separate proteins, immunoglobulins migrate to the gamma globulin region.
Therefore, the plasma proteins known as antibodies are correctly identified as gamma globulins.

Option A: Fibrin is an insoluble protein that forms the final clot during blood coagulation. It is not an antibody.
Option B: Thrombin is an enzyme that catalyzes the conversion of fibrinogen to fibrin during blood clotting. It is a coagulation factor, not an antibody.
Option C: Albumins are the most abundant plasma proteins, but their primary roles are maintaining osmotic pressure and transporting substances. They do not have antibody functions.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Classification and function of plasma proteins, specifically identifying the protein class for antibodies as background academic context rather than a clinical decision trigger.
Measuring gamma globulin levels is clinically important. Elevated levels (hypergammaglobulinemia) can indicate chronic infections, autoimmune diseases, or multiple myeloma (a cancer of plasma cells).
Low levels (hypogammaglobulinemia) suggest an immunodeficiency, increasing the patient's susceptibility to infections. These patients may require immunoglobulin replacement therapy.
Nurses may administer intravenous immunoglobulin (IVIG), which is a preparation of gamma globulins, to treat patients with immune deficiencies or certain autoimmune conditions.

How to Approach the Question

First, identify the core concepts in the question: 'plasma protein' and 'antibodies'.
The question asks for the specific classification of antibodies within the group of plasma proteins.
Recall the major types of plasma proteins: albumin, globulins (alpha, beta, gamma), and fibrinogen.
Consider the function of each option. Fibrin and thrombin are related to blood clotting.
Albumin's main role is maintaining osmotic pressure and transport.
This leaves globulins. Recall that antibodies are also called immunoglobulins and are the primary agents of humoral immunity.

Concept Tested & Keywords

Concept Tested: Classification and function of plasma proteins, specifically identifying the protein class for antibodies.
Stem keywords: plasma protein, antibodies
Lead-in keywords: are

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Practise the full NVS- 2025

Attempt every question from this paper in a timed mock, then review the full solution for each one.