protists - probably developed due to endosymbiosis 

• most diverse kingdom in Eukarya domain
• symbiotic/aerobic bacteria >> mitochondria
  • most similar to nonsulfur purple bacteria
  • proteins for respiration embedded within folds of membrane
• symbiotic/photosynthetic bacteria >> chloroplasts
  • 3 different classes of chloroplasts (red, green, algae) >> separate paths of evolution
• mitochondria/chloroplasts both have their own circular DNA
  • replicates through splitting
  • similar size/membrane structure as prokaryotes
• evolution of mitosis/cytokinesis not shown in any way
• about 60 protists don’t have definite places on the phylogeny tree

general protist characteristics - non-fungi, non-plant, non-animal eukaryotes 

• unicellular/multicellular, some form colonies
• cell surface - ranges from simple plasma membrane to extracellular material deposits
• locomotor organelles - provides mov’t
  • mainly through flagella (single or cilia) or pseudopodial (false foot) mov’t
  • lobopodia - large pseudopods used by amoeba
  • filopodia - thin, branching pseudopods
  • axopodia - supported by microtubules to move through extension/retraction
• cyst formation - dormant forms of cells w/ resistant outer coverings
  • cell metabolism shuts down
• nutrition - only chemoautotrophic nutrition not used (only found in prokaryotes)
  • phototrophs - photosynthetic
  • phagotrophs - ingests visible food particles
  • osmotrophs - ingests food in soluble form
• reproduction - usually asexual
  • sexual reproduction during times of stress
  • binary fission - cell splits in 2
  • budding - fission where new cell is much smaller than parent
  • schizogony - multiple fission