stressed out before exam.

CAteCHOlamine:
acts at beta1 to cause increase in heart rate (chronotropic)
acts at alpha1 to cause vasoconstriction
acts at beta2 to cause vasodilation & bronchodilation
=> run away from the lion => needs vasodilation in peripheral vessels to run away from other lions, also bronchodilation to breathe better

The end results is the balance of everything.