welcome to the Biology section.  At last it is finished. Where there are several songs or videos that are down for one concept do let me know which one helps you best. Some are fairly basic for those of you who struggle with the subject whilst others go further for those of you who like a challenge. 

Enjoy

ABT

Technical Info

The videos on this web site are avi files encoded using the xvid codec.  this codec and many others can be downloaded and installed from a variety of web sites the K lite codec pack is very useful. The videoLan player is an open source player that will also play almost any video file and is available for at least 19 different operating systems.  For ipad download VM player HD lite. This will allow you to watch videos up to 30 minutes long. For longer videos you will need to buy the full version.