Chrysophytes Chrysophytes are another division of algae. They contain chlorophyll but also possess a carotenoid (pigment) called fucoxanthin which gives them a yellow-brown color. Unlike the euglenas, chrysophytes have rigid cell walls which are often strengthened by silicon compounds. An additional distinction between chrysophytes and euglenas is that chrysophytes store their food as oils, whereas euglenas utilize starch.
Many varieties of chrysophytes have flagella, although there are those which do not. They usually live in marine (ocean) environments. Chrysophytes generally reproduce asexually, although some types reproduce sexually through a process called meiosis.
Pyrrophytes The third and final class of unicellularalgae which we will discuss is the division pyrrophyta. Pyrrophytes, also known as dinoflagellates, have a rigid cell wall made of cellulose unlike the cell walls of chrysophytes which contain silicon compounds. They usually have two flagella. In addition, pyrrophytes are also notable in that they are bioluminescent; that is, they naturally glow in the dark!
Pyrrophytes store their food as both starch and oil, whereas euglenas and chrysophytes utilize only one of these methods. They are usually found in marine environments, and they usually reproduce asexually through mitosis.
