PROTISTAReading AssignmentPROTISTAPROTISTA DIVERSITYHuman Diseases caused by ProtistsMALARIAComplex life cycle of PlasmodiumProtists role in food chainClassification of ProtistaSlide Number 10Slide Number 11Electron MicroscopyProtista is a Paraphyletic GroupSlide Number 14Mitochondria & Chloroplasts Origin of mitochondria and chloroplasts by endosymbiosisCiliatesIngestive FeedingA pair of Tetrahymena cells matingBiological species & Mating typesVocabularyLecture 10 Exam 1 UIC BioS 101 Nyberg1PROTISTAEukaryotes →membrane bound nucleus, mitochondria in cytoplasm. A diverse collection of eukaryotes that are NOT animals, plants or fungi. Most live in water.Lecture 10 Exam 1UIC BioS 101 Nyberg2Reading Assignmentz Reading Assignment is Chapter 29 up to section 29.4.z Figure 29.1 emphasizes how little molecular diversity there is among plants, animals and fungi compared to that within protists.z What does paraphyletic mean?Lecture 10 Exam 1UIC BioS 101 Nyberg3PROTISTAz Includes some algae, e. g., kelp, that grow to huge size as well as many species that are microscopic.z Newly discovered – protista that are smaller than bacteria living in the ocean (via direct sequencing).z Includes both free-living and parasitic forms.z Most are only found in water, i.e., aquatic.Lecture 9 Exam 1UIC BioS 101 Nyberg4PROTISTA DIVERSITYz 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.Lecture 9 Exam 1UIC BioS 101 Nyberg5Human Diseases caused by Protistsz Major Lineage Genus Diseasez Alveolata Plasmodium Malariaz Excavata Trypanosoma Sleepingsicknessz See Table 29.1 (p522) for other diseases caused by protists.Lecture 9 Exam 1UIC BioS 101 Nyberg6MALARIAz One of most important human diseases.z Complex life cycle, two hosts.z Mosquito is the “vector” that transmits the Plasmodium to humans.z Morphologically different stages live in liver and red blood cells.z Fertilization in Plasmodium takes place in Anopheles mosquito.Complex life cycle of PlasmodiumLecture 9 Exam 1UIC BioS 101 Nyberg7Lecture 9 Exam 1UIC BioS 101 Nyberg8Protists role in food chainz Ocean food chain (Fig 29.5). z Wastewater treatment involves aerobic growth of bacteria and consumption of the bacteria by ciliates and other protista.z Clarity of the water improves as the smaller cells are converted into larger cells of ciliates.z Ciliates are eaten by micro-crustaceans etc.Lecture 9 Exam 1UIC BioS 101 Nyberg9Classification of Protistaz Studies with the light microscope can only resolve structures larger than 0.5 μm.z Electron microscopes resolve structures much smaller and have lead to discoveries of similarities that were not seen using light.z Phylogenies are most unambiguously determined using molecular data.Lecture 9 Exam 1UIC BioS 101 Nyberg10Lecture 9 Exam 1UIC BioS 101 Nyberg11Lecture 9 Exam 1UIC BioS 101 Nyberg12Electron MicroscopyScanning EMof ParameciumTransmission EMCross-section ofCilia/flagellaLecture 9 Exam 1UIC BioS 101 Nyberg13Protista is a Paraphyletic Groupz Eukarya are divided into 7 major lineages based on SSU RNA sequences (Fig 29.7).z 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).Lecture 9 Exam 1UIC BioS 101 Nyberg14Fungi and animals would be in Opisthokonta, if we insisted on monophyletic groups.Lecture 9 Exam 1UIC BioS 101 Nyberg15Mitochondria & Chloroplastsz 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.z Chloroplasts are present in many types of cells.– They also generate ATP by electron transport.z Mitochondria and Chloroplasts are the only organelles with their own DNA. They make their own ribosomes.Lecture 9 Exam 1UIC BioS 101 Nyberg16Origin of mitochondria and chloroplasts by endosymbiosisz 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 DNAz Alternative?: The organelles arose by selection on nuclear genome of eukaryotes.Lecture 9 Exam 1UIC BioS 101 Nyberg17Ciliatesz Parameciumz Tetrahymenaz Stentorz The fish disease, “ich”, is caused by a ciliate.Lecture 9 Exam 1UIC BioS 101 Nyberg18Ingestive FeedingLecture 9 Exam 1UIC BioS 101 Nyberg19Chapter 27A pair of Tetrahymena cells matingLecture 9 Exam 1UIC BioS 101 Nyberg20Biological species & Mating typesFigure 29-20A life cycle dominated by haploid cells (species shown here is the dinoflagellate Gynodinium fuscum)A life cycle dominated by diploid cells (species shown here is the diatom Cyclotella meneghiniana)ASEXUALREPRODUCTION (offspring produced by mitosis)(n)(n)SEXUALREPRODUCTION (offspring produced by meiosis)Maturecell(n)Zygote(2n)Maturecell(2n)Zygote(2n)Gametes(n)DiploidHaploid(2n)MEIOSISASEXUALREPRODUCTION (offspring produced by mitosis)SEXUALREPRODUCTION (offspring produced by meiosis)MEIOSISFERTILIZATIONMITOSISMITOSISMITOSISGROWTHFERTILIZATIONLecture 9 Exam 1UIC BioS 101 Nyberg21Vocabularyz Paraphyleticz Aquaticz Matingz Direct sequencingz Complex life cyclez Endosymbiosisz Vectorz Malariaz Ingestive feedingz