MCQsOnline - Online Collection of MCQs of Medical PG Entrance Exams.

MCQ stands for Multiple Choice Questions sometimes called as Objective type questions. Here we discuss the Old Question Papers, High Yield Points and Strategies with respect to the Indian Medical Post Graduate PG Entrance Exams like AIIMS,AIPG, JIPMER, CMC Vellore, PGI Chandigarh, UPSC, TNPSC, State PG Exams like Tamil Nadu PG (TN PG), Delhi PG, UPPG, Tamilnadu PG (TNPG), Karnataka PG, MAHE, COMED-K etc.

Target PG

PG Preparation

Related Portals

Search This Site

If you cannot locate what you want to find, please search using the box given below

Wednesday, January 09, 2008

Phagocytosis - Respiratory burst involves the activation of Oxidase

032. During phagocytosis, the metabolic process called respiratory burst involves the activation of:

1. Oxidase

2. Hydrolase

3. Peroxidase

4. Dehydrogenase


1. Oxidase


Chaterjee 6th Edition Page 18

Robbins 7th Edition Page 60





Most books


The pivotal role of the respiratory burst (which follows within seconds after phagocytes are activated) in the subsequent effective killing of catalase-positive microbes became evident from studies of patients with Chronic Granulomatous Disease.


The NADPH oxidase that catalyzes the respiratory burst is found exclusively in phagocytes and remains dormant unless activated by a variety of particulate and soluble stimuli, such as opsonized microbes and chemotactic peptides.


These stimuli excite a transmembrane electron transport system in which NADPH on the cytoplasmic side of the membrane reduces oxygen through a series of reactions involving flavin adenine dinucleotide (FAD), several soluble cofactors, and membrane-associated cytochrome b. Oxygen is reduced through a univalent reduction to superoxide anion and is rapidly mutated to hydrogen perioxide and hydroxyl radicals.


The H2O2-MPO-Halide system is the most efficient bactericidal system in neutrophils

No comments:

Post a Comment