1	PROTISTA Eukaryotes →membrane bound nucleus, mitochondria in cytoplasm. A diverse collection of eukaryotes that are NOT animals, plants or fungi. Most live in water.
2	Reading Assignment Reading Assignment is Chapter 29 up to section 29.4. Figure 29.1 emphasizes how little molecular diversity there is among plants, animals and fungi compared to that within protists. What does paraphyletic mean?
3	PROTISTA Includes some algae, e. g., kelp, that grow to huge size as well as many species that are small. Newly discovered – protista that are smaller than bacteria living in the ocean (direct sequencing). Includes both free-living and parasitic forms. Most are only found in water, i.e., aquatic.
4	PROTISTA DIVERSITY Protista do NOT have the metabolic diversity of Archaea and Bacteria so they are not crucial for biogeochemical cycles, but they do have: Great structural diversity, Highly complex life cycles, especially as parasites Phylogenetic, feeding and sexual diversity.
5	Human Diseases caused by Protists Major Lineage Genus Disease Alveolata Plasmodium Malaria Discicristata Trypanosoma Sleeping sickness See Table 29.1 (p597) for others
6	MALARIA One of most important human diseases. Complex life cycle, two hosts. Mosquito is the “vector” that transmits the Plasmodium to humans. Morphologically different stages live in liver and red blood cells. Fertilization in Plasmodium takes place in Anopheles mosquito.
7	Complex life cycle of Plasmodium
8	Protists role in food chain Ocean food chain (Fig 29.5). Wastewater treatment involves aerobic growth of bacteria and consumption of the bacteria by ciliates and other protista. Clarity of the water improves as the smaller cells are converted into larger cells of ciliates. Ciliates are eaten by micro-crustaceans etc.
9	Classification of Protista Studies with the light microscope can only resolve structures larger than 0.5 μm. Electron microscopes resolve structures much smaller and have lead to discoveries of similarities that were not seen using light. Phylogenies are most unambiguously determined using molecular data.
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12	Electron Microscopy
13	Protista is a Paraphyletic Group Eukarya are divided into 8 major lineages based on SSU RNA sequences (Fig 29.8). Most protista groups have relatively few species. Because the collection labeled Protista does not include ALL the branches of a node (place where branches meet) Protista is called paraphyletic (biologists prefer monophyletic groups, but it will be hard to find an agreeable name for animals and fungi).
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15	Mitochondria & Chloroplasts Mitochondria are present in all eukaryotic cells. They are the ‘powerhouse’ of cells –the place where ATP is generated by transfer of electrons to oxygen. Chloroplasts are present in plant cells. They also generate ATP by electron transport. Mitochondria and Chloroplasts are the only organelles with their own DNA. They make their own ribosomes.
16	Origin of mitochondria and chloroplasts by endosymbiosis The endosymbiosis theory is that both organelles arose by capture of bacteria by eukaryotes. Similar size and similar ribosomes Double membrane which suggests membranes from engulfer and engulfee remain present. Both organelles have own DNA Alternative: The organelles arose by selection on nuclear genome of eukaryotes.
17	Ciliates Paramecium Tetrahymena Stentor The fish disease, “ich”, is caused by a ciliate.
18	Ingestive Feeding
19	A pair of Tetrahymena cells mating
20	Biological species & Mating types
21	Vocabulary Paraphyletic Aquatic Mating Direct sequencing Complex life cycle Endosymbiosis Vector Malaria Ingestive feeding Symbiosis