- A very simple diagram to show which ion channels are involved in the various phases of atrial contraction.

-

-

- How can the stomach flu make us lactose intolerant? How do we absorb the food we eat? Learn how the small intestine has specialized sites to break down and a...

- How can the stomach flu make us lactose intolerant? How do we absorb the food we eat? Learn how the small intestine has specialized sites to break down and a...

- Understand how nutrients and oxygen get to liver cells in a beautiful, organized manner. By Raja Narayan. More free lessons at: http://www.khanacademy.org/vi...

- Understand how the digestive tract has a mind of its own and uses neuronal as well as hormonal signals to breakdown food. By Raja Narayan. More free lessons ...

- A beautifully illustrated walk through the alimentary canal. See the entire gastrointestinal tract on a single page!