Is blood pressure the product of the stroke volume times the heart rate, the number of layer of blood in laminar flow models, the measure of force blood exerts against blood vessels walls, or the viscosity of the blood and resistance to blood flow?
Blood pressure is the measure of force blood exerts against blood vessels (arteries) walls.
Blood pressure can also be expressed as the product of the cardiac output times the peripheral vascular resistance.
The blood pressure is expressed like this : 120/80 mm (Hg) . The "120" is the measure of pressure exerted on arterial wall by flowing blood during systole of the cardiac cycle. The "80" is during diastole of the cardiac cycle. And the ''mm (Hg)'' means millimeter of mercury pressure.