Chloroplasts of certain algal taxa such as Euglenophyta are surrounded by three membranes while, Heterokontophyta and Cryptophyta have four membranes. The chloroplasts present in these organisms is a result of secondary endosymbiotic events. All of them have chlorophyll a. However, Euglenophyta uses chlorophyll b as an accessory pigment, whereas Heterokontophyta and Cryptophyta use chlorophyll c. Assuming gain-of-fun