Question

Oral efficacy of Sabin Polio Vaccine can be adequately explained by which of the following processes of absorption?

• A. Passive diffusion
• B. Active transport
• C. Ion ‐ pair transport
• D. Pinocytosis

Answer 1

The Correct Option is D

The question pertains to the oral efficacy of the Sabin Polio Vaccine and how it is absorbed. The correct answer to this question is Pinocytosis.

Let's break down the options to understand why pinocytosis explains this process adequately:

1. Passive Diffusion: This involves the passive movement of molecules from an area of higher concentration to an area of lower concentration, without the use of energy. Small, nonpolar molecules generally move in this manner. However, vaccines, such as the Sabin Polio Vaccine, cannot be absorbed via passive diffusion due to their complex and large structure.
2. Active Transport: This process involves the movement of molecules across a membrane from a region of lower concentration to a region of higher concentration using energy in the form of ATP. This typically involves specific transport proteins, which does not adequately describe the absorption of large vaccine particles.
3. Ion-Pair Transport: This involves the transport of molecules in their ionic form. Vaccines do not typically form ion pairs as they are complex protein structures, making this option unsuitable.
4. Pinocytosis: This is the process of cellular drinking where cells engulf extracellular fluid, including dissolved nutrients and small particles. As vaccines like the Sabin Polio Vaccine contain viruses that are larger in size, pinocytosis is the more appropriate mechanism. It is a special type of endocytosis in which cells internalize fluids and macromolecules from the outside environment, encapsulating them in vesicles.

Thus, pinocytosis is the process by which large particles, like those found in the Sabin Polio Vaccine, are absorbed into the cells, explaining its oral efficacy.