I created this PPT to go along with the Digestive System Open Notes (sold under separate cover in my store) but it can be used on its own without any notes as well. It's visually stimulating with loads of color pictures and animations. This PPT allows the teacher to circulate the classroom without being tethered to the board with notes. I love it!
It's also pretty comprehensive - future assignments can be completed from this PPT. This PPT is also included in the Digestive System/Nutrition bundled unit in my store.
I use this PPT and/or the Digestive System Open Notes as a study guide for a test (one less thing I have to create).