The blue bowl-like structure above is a cross section of an alveolus of the lung. Alveolar macrophages reside there that wait to pick up foreign invaders, such as the anthrax spore pictured above.

This illustration was done by Alex Katos using Photoshop and Corel Draw.

This image is copyright protected by Alex Katos and is only to be used with permission by Alex Katos. Usage rights may be purchased.