strong emotion makes the heart beat more/harder... with endorphins or enzymes or...
Close enough. It's epinephrine, a.k.a. Adrenalin, and various other activators of the Sympathetic Nervous System, giving rise to what's more commonly known as the "fight-flight-or-fright reaction." (I leave it to the reader to decide which one it is when you see your heart's desire.) The heart pounds and races, the nostrils flare, eyes dilate, blood vessels constrict, pressure rises, and a host of more subtle effects also take place, and the body is ready for action of whatever kind. The effect is diminished by the "beta-blockers" such as Lopressor and Inderal and Toprol and Corgard and atenolol and several other names besides. Take heed, all ye high blood pressure and angina sufferers.
Officially it isn't called "Adrenalin" these days, mainly because decades ago some pharmaceutical outfit copyrighted the scientific name and got the medical community so up in arms over the sheer effrontery that they went and translated it from Latin to Greek {Adrenalin = ad + renal = the gland above the kidney = epi + nephros = epinephrine, its modern name} so's Not to Use That Name any more. That showed 'em!
Now aren't you glad you asked?
