Farbgrafik
1: Blutfluss, 2: Klappe. Querschnittsdiagramm einer Vene mit Klappen.
(CC BY-derivative work: Mouagip (talk) SA 3.0
Schwarz-weiß-Foto
Microvessel showing an erythrocyte (E), a tunica intima of endothelial cells and a tunica adventitia of pericytes.
(CC BY Robert M. Hunt 3.0
Farbgrafik
This slide shows the arterial and venous blood circulation of the pulmonary system.
CC BY Artwork by Holly Fischer
3.0
http://creativecommons.org/licenses/by/3.0/deed.de