Recognition and digestion by phagocytosis due to coated surface of pathogens by antibodies is

Options

A. Opsonisation
B. B-ce'i immunisation
C. T-cell immumisation
D. Complement fixation

Answer

**Step-by-Step Solution:**

1. **Understanding Opsonization**: Opsonization is a crucial immune process where pathogens are marked for destruction. This marking is done by antibodies, which are a type of opsonin.

2. **Binding of Antibodies**: The antibodies bind to specific sites on the surface of the pathogen, known as epitopes. This binding is essential as it signals to the immune system that the pathogen needs to be targeted.

3. **Attraction of Phagocytes**: Once the antibodies have coated the pathogen, they attract phagocytes (a type of immune cell) to the site of infection. The presence of the opsonin (antibody) makes it easier for phagocytes to recognize and bind to the pathogen.

4. **Engulfment of Pathogen**: The phagocytes then engulf the pathogen in a process called phagocytosis. This involves the phagocyte surrounding the pathogen and internalizing it into a compartment within the cell.

5. **Digestion of the Pathogen**: After engulfment, the pathogen is enclosed in a vesicle called a phagosome. This vesicle then fuses with lysosomes, which contain digestive enzymes. The enzymes break down the pathogen, effectively digesting it.

6. **Elimination of the Pathogen**: Finally, the digested components of the pathogen are either presented on the surface of the phagocyte (to alert other immune cells) or expelled from the cell, completing the immune response.

**Final Answer**: The process described is known as **opsonization**, which enhances the recognition and digestion of pathogens by phagocytes through the coating of pathogens with antibodies.

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