ENZYME catalyzed reactions

Watch the difference between an enzyme catalyzed reaction and a reaction that takes place without an enzyme. Which reaction takes a longer time?
http://www.stolaf.edu/people/giannini/flashanimat/enzymes/prox-orien.swf

ENZYMES video clip

This short video clip is a very good visual explanation on how enzymes work.
http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_enzymes_work.html

ENZYMES animation

http://student.ccbcmd.edu/~gkaiser/biotutorials/proteins/enzsub.html