I woke up too late for class, so here is how I studied!
I learned about respiration:
http://www.youtube.com/watch?v=nkRcdfmHqqI
I learned about circulation:
http://www.youtube.com/watch?v=CRfrQXrLkDc
I learned about energy:
http://www.youtube.com/watch?v=QYyU6KZJ32k