Understanding the detailed mechanisms of photosynthesis has become an ever increasingly important research field, as the community aims to apply the understandings from nature to design elements in organic photovoltaics. This thesis is a comprehensive study of the optical properties and the critical role of phycobiliproteins in the absorption of green light for photosynthesis in cryptophyte algae (Rhodomonas CS24 and Chroomonas CCMP270). Investigations of two different isolated proteins, phycoerythrin 545 and phycocyanin 645, are described in addition to investigating the workings of these...