Chlamydomonas is a model organism for research into flagellar motility, chloroplast dynamics, biogenesis, and genetics. Chlamydomonas have ion channels (channelrhodopsins) that are directly activated by light, which is one of its many distinguishing features.
The pulmonary veins transport oxygenated blood back to the heart from the lungs, while the pulmonary arteries move deoxygenated blood from the heart to the lungs.)
