1. there are 3 main categories of etiology
1.1. inttrinsic
1.1.1. cause of disease coming from within the subject
1.2. extrinsic
1.2.1. cause of disease comes from external components
1.3. idiopathic
1.3.1. cause of disease unknown
2. Major causes of disease:
2.1. inflammatory
2.1.1. caused by: disease-causing agents
2.1.1.1. Bacteria
2.1.1.1.1. Bad bacteria
2.1.1.1.2. Some bacteria is good and some is bad
2.1.1.2. viruses
2.1.1.2.1. transferred person to person
2.1.1.2.2. transferred animal/insect to person
2.1.1.3. prions
2.1.1.3.1. small substance made of protein with no nucleic acid
2.1.1.3.2. replicate and cause infection
2.1.1.4. fungi
2.1.1.4.1. yeast and mold
2.1.1.4.2. most harmless but some harmful
2.1.1.4.3. harmful
2.1.1.5. protists
2.1.1.5.1. parasites that can live in human bodies
2.1.1.5.2. transferred by contaminated food, water or fecal matter
2.1.1.5.3. transferred insect to human
2.1.1.5.4. transferred human to human
2.2. immune disorders
2.2.1. occurs when the body's immune system attacks it's own cells
2.2.1.1. Example: rheumatoid arthritis
3. etiology
3.1. the cause of a disease
3.2. the "why"
3.3. lesion
3.3.1. the root of a cause
3.3.1.1. Possibilities include: a damaged gene or enzyme, abnormal cells, tissues, or organs