Characteristics of free radicals
Which of the following is the characteristics of radicals?
In chemistry, a free radical is an atom, molecule, or ion that has at least one unpaired valence electron. With some exceptions, these unpaired electrons make radicals highly chemically reactive. Many radicals spontaneously dimerize. Most organic radicals have short lifetimes.
What characterizes a free radical quizlet?
What are free radicals? Highly unstable atoms, molecules or complexes with one or more unpaired electrons, resulting from electron loss during oxidation. Free radicals are often uncharged and highly reactive.
How are free radicals classified?
According to the classification proposed, the radicals may be divided into primary (superoxide, semiquinones and nitric oxide), secondary (hydroxyl and lipid radicals) and tertiary (radicals of antioxidants).
What is the function of free radicals?
Free radicals and oxidants play a dual role as both toxic and beneficial compounds, since they can be either harmful or helpful to the body. They are produced either from normal cell metabolisms in situ or from external sources (pollution, cigarette smoke, radiation, medication).
What are free radicals how are they formed give an example?
A radical is a chemical entity with an unpaired electron in it. A radical can be electrically neutral, radical cation charged positively, or radical anion charged negatively. Example: In ultraviolet light, the chlorine molecule Cl2 undergoes homolysis to form two radicals of Cl.
What causes free radicals quizlet?
What are free radicals and how are they produced? Produced by oxygen, light, and heat redox reactions– pollution, UV light, tobacco smoke. Free radicals are damaging to cells and can cause oxidation and lead to an unpaired electron (unstable).
What are free radicals in simple terms?
(free RA-dih-kul) A type of unstable molecule that is made during normal cell metabolism (chemical changes that take place in a cell). Free radicals can build up in cells and cause damage to other molecules, such as DNA, lipids, and proteins. This damage may increase the risk of cancer and other diseases.
What are free radicals in human body?
Free radicals are unstable atoms that can damage cells, causing illness and aging. Free radicals are linked to aging and a host of diseases, but little is known about their role in human health, or how to prevent them from making people sick.
What creates free radicals?
Free radicals are highly reactive and unstable molecules. They are made by the body naturally as a byproduct of normal metabolism. Free radicals can also be made after exposure to toxins in the environment such as tobacco smoke and ultraviolet (UV) light.
What is a free radical quizlet nutrition?
what is a free radical? a highly unstable atom with an unpaired electron on its outermost shell–when a free radical comes in contact with important cells (DNA, cell membranes, LDL’s, and cell proteins) it can kill it or cause it to stop working properly.
What is a radical in chemistry quizlet?
Definition. 1 / 51. An atom or molecule that has one or more unpaired electrons.
Do free radicals damage the cells mitochondria?
Once generated, free radicals can directly impair mitochondrial structure and function. A decline in mitochondrial respiratory function along with an insufficient supply of energy can significantly increase mitochondrial free radical production (Van Houten et al., 2006; Lee et al., 2007).
What contributes to the ozone hole quizlet?
Ozone depletion occurs when chlorofluorocarbons (CFCs)—formerly found in aerosol spray cans and refrigerants—are released into the atmosphere.
Which of the following disease has not been linked to free radical damage?
Quizz 5 Chap 8
| Question | Answer |
|---|---|
| Which of the following foods are the richest sources of vitamin E? | vegetable oils, nuts, and seeds |
| Which of the following diseases has Not been linked to free radical damage? | type 1 diabetes |
Where does cell mitosis occur Milady?
Also known as basal cell layer; active layer of the epidermis above the papillary layer of the dermis; cell mitosis takes place here that produces new epidermal skin cells and is responsible for growth.
What causes ozone depletion?
Ozone depletion occurs when chlorofluorocarbons (CFCs) and halons—gases formerly found in aerosol spray cans and refrigerants—are released into the atmosphere (see details below).
What is the main cause of ozone hole?
Reasons for the ozone hole
The ozone hole has developed because people have polluted the atmosphere with chemicals containing chlorine and bromine. The primary chemicals involved are chlorofluorocarbons (CFCs for short), halons, and carbon tetrachloride.
Where is ozone hole situated?
Antarctica
What we call the ozone hole is a thinning of the protective ozone layer in the stratosphere (the upper layer of Earth’s atmosphere) above Antarctica that begins every September. Chlorine and bromine derived from human-produced compounds are released from reactions on high-altitude polar clouds.