Stress is a biological and psychological response experienced on encountering a threat that we feel we do not have the resources to deal with.
A stressor is the stimulus (or threat) that causes stress, e.g. exam, divorce, death of loved one, moving house, loss of job.
Sudden and severe stress generally produces:
-Increase in heart rate
-Increase in breathing (lungs dilate)
-Decrease in digestive activity (don’t feel hungry)
-Liver released glucose for energy
Hope this helps :-)