"Purple Pages" videos

Here are six videos regarding macromolecules, a major part of the Purple Pages.

I didn't have access to good quality images from Biology:  EDL (2nd ed.) but I believe all of these images are owned by Nelson Education … they're the basis for the first edition's videos, so we should be in good shape copyright-wise.  I'd like to know if they're of sufficient quality or if you want them changed.  I can easily make some chemistry ones (structure of atoms, features of water, types of bonds).

I've added a new section:  Atoms and Small Molecules

Introduction:

Atoms and small molecules:

Macromolecules: