They have membrane-bound organelles (including mitochondria and chloroplast), cytoskeleton, pseudopodia for movement, undergo meiosis, and can be unicellular or multicellular. They also have a flexible cell surface to be heterotrophic. Mitochondria are the same size as alpha- proteobacteria, they replicate via fission, have their own ribosomes, have two membranes, and have a similar genome sequence to proteobacteria. Chloroplasts also likely evolved this way (originally cyanobacteria) but from secondary symbiosis (4 membranes). What are three of the protist innovations: structures for support and protection: diatom, dinoflagellate, and foraminifera, sexual reproduction via meiosis and syngamy: produces more viable offspring, advantageous in stressful environments, multicellularity: cell communication, specialization, and adhesion. List the important uses of protists and kelp in the ocean. Pathogens and parasites (plasmodium causes malaria, water mold and potato famine) Marine food chains, source of limestone, component of petroleum and sedimentary rock, can cause algal blooms, carbon cycle!