FreeRadicals_and_ReactiveOxygenSpecies - The Physiology of...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
1 The Physiology of Hyperbaric Oxygen Therapy Free Radicals and Reactive Oxygen Species I. Introduction – Definition, Source, function and Purpose A. Definition of free radicals and r eactive o xygen s pecies (ROS). 1. Reactive oxygen species (ROS) are highly reactive ions and “free radicals” (chemicals containing atoms with an unpaired electron in its outer orbit) involving oxygen molecules. 2. “Free radicals” are present that do not contain oxygen, but ROS refers to free radicals containing oxygen molecules. 3. Characteristics: a. Short lived b. Unstable c. React with other molecules to achieve stability B. Source of ROS’s 1. Byproduct of cellular respiration (presence of redox cycling compounds). 2. Synthesized by enzyme systems – phagocytic cells, neutrophils and macrophage (NADPH oxidase, myeloperoxidases). 3. Exposure to ionizing radiation 4. Smoking, herbicides, pesticides, fried foods, etc. 5. Production: a. Chain reaction, a free radical steals an electron from a nearby compound forming a new free radical. Free radicals may steal electrons from cellular structures or molecules. b. By normal cellular respiration – electron transport system – often oxygen is the terminal electron acceptor in the cell mitochondria Æ ROS c. Figure on production of common free radical species.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2 C. Function and purpose 1. Necessary for production of some hormones (thyroxine). 2.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 01/16/2012 for the course BI 200 taught by Professor Potter during the Fall '11 term at Montgomery College.

Page1 / 5

FreeRadicals_and_ReactiveOxygenSpecies - The Physiology of...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online