(a) The force that is exerted by blood against the wall of a vessel is called blood pressure. (b) The pressure of blood caused inside the artery during the ventricular systole that is  contraction is called systolic pressure. The normal systolic pressure is about 120 mm of Hg (c)The pressure in the artery caused during ventricular diastole relaxation is called diastolic pressure. The normal diastolic pressure is 80 mm of Hg