General Causes of Disease

 GENERAL CAUSES OF DISEASE

Human disease results from the action of various in-jurious agents on cells and tissue, causing biochemi-cal or structural damage. Disease may be caused by:

 

·           Impaired energy production (e.g., reduced nu-trition or reduced availability of oxygen to tis-sues)

 

·           Impaired immune responses

 

·           Genetic abnormalities inherited from a parent or acquired by radiation, viruses, drugs, or chemicals

 

·           Metabolic toxic agents such as alcohol, drugs, and heavy metals

 

·           Physical agents (e.g., mechanical trauma, heat and cold, radiation injury)

 

·           Chemical agents such as industrial and agricul-tural chemicals and toxic waste

 

·           Infectious agents

 

·           Abnormal development and growth.

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