Carbon dioxide diffuses out of the tissues and into the blood, where it is dissolved in the plasma. While some of the carbon dioxide remains dissolved in the plasma, most carbon dioxide diffuses into our red blood cells.
A screencast is a digital movie in which the setting is partly or wholly a computer screen, and in which audio narration describes the on-screen action. It's not a new idea.
Here are some of the ways screencasts are used. Tutorial: A screencast that demonstrates how to use an application or service. The screencasts on my LibraryLookup page are examples of tutorials. One of the most dramatic examples of this genre is called Cracking WEP in 10 minutes.