Question

Events in body defence against infection are

• A. Inflammation, Chemotaxis, Diapedesis, Phagocytosis and Digestion
• B. Inflammation, Diapedesis, Chemotaxis, Phagocytosis and Digestion
• C. Digestion, Diapedesis, Phagocytosis, Chemotaxis and Inflammation
• D. Diapedesis, Chemotaxis, Digestion, Phagocytosis and Inflammation

Answer 1

The correct option is B Inflammation, Diapedesis, Chemotaxis, Phagocytosis and Digestion

Events in body defence against infection are :

• Inflammation is defined as the early response to local injury in a vascularized tissue. The five classical signs of inflammation are heat, pain, redness, swelling, and loss of function.
• Diapedesis is the passage of blood cells through the intact walls of the capillaries, typically accompanying inflammation.
• The movement of leukocytes (most commonly neutrophils) from the blood vessel lumen into a damaged area is called chemotaxis and is mediated by substances known as chemotactic factors, that diffuse from the area of tissue damage.
• Phagocytosis is a process where macrophages or neutrophils ingest solid particles. The first step in phagocytosis is adhesion of the particle to be phagocytosed to the cell surface. This is facilitated by opsonization. The phagocyte then ingests the attached particle by sending out pseudopodia around it. These meet and fuse so that the particle lies in a phagocytic vacuole (phagosome) bounded by a cell membrane.
• Lysosomes contain proteolytic enzymes, fuses with the phagosome and facilitate intracellular killing (digestion) of micro-organism.

So, the correct answer is 'Inflammation, Diapedesis, Chemotaxis, Phagocytosis and digestion'.