PATHOLOGY: THE STUDY OF DISEASE

Disease can be defined as an impairment of health that interferes with the body’s abil-
ity to function normally. Injuries, poisonings, the introduction of foreign substances,

and environmental problems do not strictly fall into the category of disease but they
cause their own pathologies nonetheless.
As mentioned, each body system chapter contains its own section on pathology.
But here we will review some general terminology associated with disease and injury.
Let us start by looking at the roots of the word pathology. The suffix –ology means the

study of, and the prefix path– means feeling or suffering, from the Greek pathos, mean-
ing disease. There are two main types of pathology. Anatomical pathology focuses on

the study of tissues removed from a dead or living person to diagnose disease or cause
of death. Clinical pathology is actually a number of subdisciplines that are often

referred to as laboratory medicine: chemistry, histology, microbiology, and other spe-
cialties. To go even further, pathophysiology is the study of how disease and trauma

alter the normal functioning of the body.

To know what is abnormal, you must first know what is normal—not just regard-
ing disease but also regarding simple body function. You may encounter questions on

the test pertaining to normal blood pressure, normal body temperature, normal blood
pH, and so on.