North Africa, region of Africa comprising the modern countries of Morocco, Algeria, Tunisia, and Libya. North AfricaEncyclopÃ¦dia Britannica, Inc.The geographic entity North Africa has no single accepted definition.
A Stressor is anything (physical or psychological) that produces stress (negative or positive) is considered a stressor.
Stress is defined as force per unit area. It has the same units as pressure, and in fact pressure is one special variety of stress. However, stress is a much more complex quantity than pressure because it varies both with direction and with the surface it acts on.