BIO153H5 Chapter Notes - Chapter 28: Phytophthora Infestans, Oomycete, Red Algae
Document Summary
Concept 28. 1 protists are an extremely diverse assortment of eukaryotes. Protists exhibit more structural and functional diversity than any other group of organisms. Most protists are unicellular, although there are some colonial and multicellular ones. At the cellular level, many protists are very complex. This is to be expected of a single cell that must carry out the basic functions performed by all the specialized cells in a multicellular organism. Protists are the most nutritionally diverse of all eukaryotes. Some are heterotrophs, absorbing organic molecules or ingesting food. Some are mixotrophs, combining photosynthesis and heterotrophic nutrition. Protists can be divided into three groups, based on their roles in biological particles. communities. Protists include photosynthetic algal protists, ingestive protozoans, and absorptive protists. Some are exclusively asexual, while most have life cycles including meiosis and syngamy. Much of protist diversity is the result of endosymbiosis, a process in which unicellular organisms engulfed other cells that evolved into organelles in the host cell.
