Ch 28 - Protists PDF
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This chapter, labeled Chapter 28, delves into the world of protists, addressing their evolutionary history, diversity, and classification. It examines various protists including Euglenozoans, and features discussions on their characteristics and modes of nutrition. The document also covers topics such as locomotion and reproduction in these organisms.
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Happy Monday Career Fair Today Careers relating to Biology Siena 101 12nn – 2pm Food!! Botany BIO 322 Lecture and Lab Offered Summer 2025 Dr. Redway is Instructor Quiz 5 Chapters 26 and 27 Connect Opens Monday, October 7, 2...
Happy Monday Career Fair Today Careers relating to Biology Siena 101 12nn – 2pm Food!! Botany BIO 322 Lecture and Lab Offered Summer 2025 Dr. Redway is Instructor Quiz 5 Chapters 26 and 27 Connect Opens Monday, October 7, 2024 at 9am Closes Monday October 14, 2024 at 11:59pm Take home: – Work in groups for better understanding 30 minutes Protists Chapter 28 5 ta 28.1 Prokarya Domain/Kingdom: Archaea prokaryotes Domain/Kingdom: Bacteria Domain: Eukarya Kingdom: Fungi Kingdom: Protista eukaryotes Kingdom: Plantae Kingdom: Animalia Excavata Protista SAR Euglenazoa Rhizaria Radilorarius Foramifera Euglenids Kinetoplastids (Euglena) (Trypanasoma) Amoebazoa Opisthokonta SAR Alveolata Stramenopila Dinoflagellates Ciliates Apicomplexans Brown Algae Diatoms (Paramecium) (Plasmodium) Archaeplastida Rodophyta Chlorophyta Charophyta Land Plants Green: Super group Red: Group/Phylum Black: Sub-groups Protista Cladogram Protista SAR Amoebezoa Opisthokonta Excavata Rhizaria Alveolata Stramenopila Archaeplastida Euglenozoa Parabasalid Foraminifera Radiolaria Rhodophyta Chlorophyta Brown Algae Diatoms Euglenids Kinetoplastida (Phylum (Euglena) ( Trypanasoma) Chrysophyta) Dinoflagellata Apicomplexans Ciliata (Paramecium; (Plasmodium) Ceratium; Stentor; Blespharisma) Green: Super groups Red: Groups Black: Sub- groups 28.1 Eukaryotic Origins Eukaryotic cells differ from prokaryotes – Presence of a more complex cytoskeleton (microfilaments and microtubules in cytoplasm that maintains shape etc) – Compartmentalization (nucleus & organelles) Appearance of eukaryotes in microfossils occurred about 1.5 BYA Early Eukaryotic Fossil Cells: Larger than prokaryotes Thicker walls Internal membranes Origin of Nucleus and ER Nuclear envelope and ER developed from infolding of plasma membrane Nuclear envelope encased DNA to form nucleus Theory of Endosymbiosis-Evolution of Chloroplast and Mitochondria - Aerobic Bactria engulfed in ancestral eukaryote cell which then became mitochondria -Photosynthetic bacteria engulfed in ancestral eukaryotic cell which then became chloroplasts Add Figure Endosymbiosis- living together in close association (one lives inside the other) Endosymbiotic bacteria-live in host and perform specific functions for host Evol. of Brown and Red Algae 2o Endosymbiosis Cyanobacteria engulfed by eukaryotic cell to form Red algae Red Algae engulfed by cell to form Brown Algae Possible that all chloroplast derived from a single line of cyanobacteria However these organisms are not monophyletic (bacteria, protists, plantae) Monophyletic-most recent and all its descendants Evidence for endosymbiosis Endosymbiosis supported by – Many symbiotic relationships exists – Mitochondria & chloroplasts have their own circular DNA DNA similar to bacteria DNA in size & organization – Ribosomes inside mitochondria similar to bacterial ribosomes – Chloroplasts & mitochondria replicate by binary fission – not mitosis Mitosis evolved in eukaryotes 28.2: Overview of Protists United on the basis that they are not fungi, plants, or animals Have no unifying feature Most diverse of the four eukaryotic kingdoms Vary considerably – Unicellular, colonial & multicellular groups – Most are microscopic but some are huge – All symmetries – All types of nutrition Five Super groups of Protists SAR = Chromalveolata and Rhizaria combined Hence SAR: Stramenopila, Alveolata and Rhizaria OLD-Six Supergroups (Lab) Five Super groups of Protists Protists are polyphyletic (does not include most recent common ancestor) Plants, fungi and animals are monophyletic clades (most recent ancestors and all its descendants) Cell Surface Varies Absence of cell wall Euglena – Amoeba – Euglena – protein strips around plasma membrane Presence of cell wall – Cellulose-Red algae – Silica-Diatoms Diatom Locomotion in Protists Flagella – One or more to propel thru water (eg Euglena) Locomotion in Protista Cilia – Shorter & more numerous than flagella to create water currents for feeding and/or locomotion (Paramecium, Blepharisma, Stentor) Cilia 100x Stentor Cilia Paramecium 400x Locomotion in Protists Pseudopods (“false feet”) – Flowing cytoplasmic projections that pull organisms forward – Chief means of locomotion for amoebas – In others, pseudopods are long and thin, can extend or retract – Tips can adhere to surfaces – Used by other protists as well Amoeba Procedure: Protists Supergroup Amoebozoa: Chaos (live) x400 Pseudopod x100 Pseudopod Nutrition in Protists Autotrophs-produce their own food – Some photosynthetic Heterotrophs- energy from organic material from other organisms – Phagotrophs – Ingest particles of food into food vacuoles; lysosomes fuse with vacuoles and introduce enzymes that digest food, which are then absorbed Mixotrophs are both phototrophic & heterotrophic – Eg - Euglenids Reproduction in Protists Asexual reproduction – Typical mode of reproduction, but Mitosis-nuclear membrane may persist and spindles form within – Some species have an unusual mitosis Budding – daughter cell smaller than parent and then grows to adult size Schizogony – cell division preceded by several nuclear divisions; produces several individuals Some form cyst to endure harsh conditions Sexual reproduction – Some regularly reproduce sexually, some under stress – Meiosis is a major eukaryote innovation-allows diversity – Union of haploid gametes which are produced by meiosis – Advantage in allowing frequent genetic recombination Protists are Bridge to Multicellularity Multicellularity began in protists – Unicellular single – Unicellular colonial – Unicellular filamentous – Multicellular Multicellularity fosters specialization – Thallus – Well formed multicellular structure 28.3: Super group: Excavata Super group Excavata Excavata Consists of: Euglenazoa – Euglenozoans – Diplomonads Euglenids Kinetoplastids – Parabasalids (Euglena) (Trypanasoma) Characteristic: – Feeding groove looking like it was excavated from the side of their bodies Present in most groups along one side of the cell body Super group: Excavata Group: Euglenozoa Swimming motion is most distinguishing feature Bodies change shape when swimming – alternate between being stretched out & rounded up Can change shape because they lack cell walls – Strips of protein encircle cell, called pellicle Include: Excavata – free-living (Euglenids) Euglenozoa – parasitic (Kinetoplastids) Euglenids Kinetoplastids (Euglena) (Trypanasoma) Super group: Excavata Group: Euglenozoa Sub group: Euglenids Euglena – protein strips around plasma membrane-pellicle – Body shape will change when swimming Euglenids 1/3 of euglenids have chloroplasts & are autotrophic; the others lack chloroplasts, ingest their food & are heterotrophic (mixotrophs) Numerous small chloroplasts Reproduction is asexual; occurs via mitosis – Nuclear membrane remains intact throughout Super group: Excavata Group: Euglenozoa Sub group: Parasitic Kinetoplastida Unique, single mitochondrion Eg: Trypanosomes which cause human diseases – Leishmaniasis – sand fly-skin sores – African sleeping sickness (trypanosomiasis)– tsetse fly is a vector –affects CNS-can be fatal – Chagas disease – insect vector-found in dwellings of mud, straw - cardiac & digestive problems Lab: Procedure: Protists Supergroup Excavata: Supergroup Excavata: Group Euglenozoa: Euglena (slide) Group Parabasalids: Termite flagellates (slide) Supergroup Excavata: Group Parabasalids: Leishmania donovani (slide) x400 x200 Look for flagella x400 Five Super groups of Protists SAR = Chromalveolata and Rhizaria combined Hence SAR: Stramenopila, Alveolata and Rhizaria OLD-Six Supergroups (Lab) 28.4: Super group: SAR Supergroup consisting of three branches: – Stramenopila – Alveolata – Rhizaria 28.4: Supergroup: SAR: Stramenopila Supergroup consisting of three branches/groups: Chromalveolata Stramenopila Brown Algae Diatoms Super group: SAR Group: Stramenopila Sub group: Brown Algae Fucus (Sea weed) Conspicuous seaweeds Fucoxanthin Transport cells similar to phloem? Sieve tubes of phloem in Angiosperms and brown algae-Example of GiantGiant Kelp Kelp convergent evolution (Chap 23) Giant Kelp Vessel harvesting kelp-grown in deep Brown Algae Algin - Produced by giant kelps and other brown algae – Used as thickeners or emulsifiers Food-Stabilizer in Ice Cream, Milk Shake, Eggnog, coffee creamers Suspension agent-Salad Dressing, food concentrates Thickening agent-toppings, puddings Paper-better surface for ink-improves absorbency Cosmetics-Soothing agent-creams, lotions Industrial-paint Kelp contains iodine and used to treat goiter (enlarged thyroid) – Not very common in US as we use iodized salt Kelp rich in nitrogen and potassium (fertilizer) Supergroup: SAR Group: Stramenopila Sub group: Diatoms Photosynthetic, unicellular organisms Unique double shells made of silica, with many marks Human and Ecological Relevance of Diatoms Food chain-eaten by fish Oils- 40% body mass-sources of vitamins (cod and other oils) Diatomaceous earth: – light, porous, powdery, high melting point, insoluble in most acids and liquids Diatomaceous earth quarry – Filtration – Polishes, toothpaste – Paint that reflects light – Slug control 28.5: Super group: SAR Group: Alveolata Includes: – Dinoflagellates – Apicomplexans – Ciliates Super group: SAR Group: Alveolata Common Trait: Flattened sacs called alveoli stacked in layers below plasma membrane – Function: membrane transport Host Apical complex: – forces parasite into host cell Supergroup: SAR Group: Alveolates Sub group: Dinoflagellates Photosynthetic, unicellular with distinct flagella Live in aquatic environments Some are luminescent – Twinkling or flashing effect at sea at night Supergroup: SAR Group: Alveolates Sub group: Dinoflagellates Red tide/blooms: – excess nutrient from agricultural and human activity increases mitotic activity of dinoflagellates – Dinoflagellates release toxins which color sea (red, green) and can cause respiratory failure in vertebrates – Shellfish poisoning can be caused by dinoflagellate blooms – Also poisoning of birds, fish, marine mammals – Humans also affected by consuming affected fish or shellfish – paralytic shellfish poisoning These Dinoflagellates are green Aerial view Red Tide https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.nationalgeographic.co m%2Fenvironment%2Farticle%2Fred-tides&psig=AOvVaw1xr9KHBLhVm5wxzgxaurEA &ust=1645045175027000&source=images&cd=vfe&ved=0CAgQjRxqFwoTCJCp-IbNgv YCFQAAAAAdAAAAABAD Super group: SAR Group: Alveolates Sub Group: Apicomplexans Spore-forming animal parasites Apical complex is a unique arrangement of organelles at one end of the cell – Enables the cell to invade its host Plasmodium-causes malaria – Human and mosquito vectors Plasmodium life cycle Super group: SAR Group: Alveolates Sub group: Ciliates Large numbers of cilia arranged in longitudinal rows or spiral around cell – Beat in a coordinated fashion; can also be used for ingesting food Pellicle – tough but flexible outer covering to move around or squeeze through obstacles Have two types of vacuoles – Food vacuoles – digestion of food – Contractile vacuoles – regulation of water balance-empty content to outside of organism 2 types of nuclei – Micronucleus – used only as germ line for sexual reproduction; DNA not transcribed – Macronucleus – essential for daily functions Paramecium Other Ciliate Stentor Cilia Cilia 400x 100x 28.6 : Supergroup: SAR Group: Rhizaria Super group: SAR Group: Rhizaria Three sub-groups: – Radiolaria (marine) – Foraminifera (marine) – Cercozoa (soil) Locomotion by pseudopods – Flowing cytoplasmic projections that pull organisms forward – Some needlelike extending through silica exoskeletons – Long, thin and can adhere to surfaces – Also present in Amoebazoans Pseudopods Super group: SAR Group: Rhizaria Sub-group Foraminifera Heterotrophic marine Shells of calcium carbonate which contribute to limestone formation – White cliffs of Dover –limestone of fossilized Foraminifera As You Enter Please answer one (1) in chat: – Domain to which Protist belong – What gives Brown Algae it color – Is Brown Algae photosynthetic 28.7: Supergroup: Archaeplastida This group consists of: – Rhodophyta (Red Algae) – Chlorophyta (Green Algae) Which are the – Charophyta (Green Algae) closest relatives to Land Plants? – Land Plants Chlorophyta, Charophyta – Make up Green algae Supergroup: Archaeplastida Group: Rhodophyta (Red Algae) Multicellular, marine Phycobilin: accessory photosynthetic pigments, often red Agarose used to make Agar – Solidifier of nutrient culture media – Has consistency of gelatin – Retains moistness in bakery products – Thickens ice-cream and cosmetics – Sushi rolls Super group: Archaeplastida Group: Chlorophyta (Green Algae) Green algae consist of 2 lineages – Chlorophyta Unusual diversity & lines of specialization Eg-Chlamydomonas-Unicellular; Volvox – Unicellular colonial; Ulva- Multicellular thallus Resemble land plants esp in chl Chlamydomonas biochemistry but did not give rise to them – Charophytes Gave rise to the land plants Cell specialization in colonial Chlorophyta Multicellularity arose many times in the eukaryotes Colonial chlorophytes (Volvox) are examples of cellular specialization, an aspect of multicellularity, as Volvox - hollow sphere made up of a single layer of 500 to 60,000 individual cells each with 2 flagella Some cells reproduce asexually while others reproduce sexually Ulva is multicellular Ulva is multicellular Supergroup: Archaeplastida Group: Charophytes (Green Algae) Closest relatives to land plants. Why? Also green algae but distinguished from chlorophytes by close phylogenetic relationship to land plants – Molecular evidence from rRNA & DNA sequences Closely related due to: – Plasmodesmata – Cytokinesis – Large, non-motile egg and sperm Two clades most closely related to land plants 28.8: Super group Amoebozoa Super group: Amoebozoa Amoebas move by means of pseudopods – Pseudopods are flowing projections of cytoplasm Extend & pull the amoeba forward Engulf food particles – An amoeba puts a Pseudopod pseudopod forward & then flows into it – Microfilaments of actin & myosin are associated with these movements Most amoeba are free living – Found in the soil as well as freshwater Some are parasitic Procedure: Protists Supergroup Amoebozoa: Chaos (live) x400 Pseudopod x100 Pseudopod Plasmodial slime molds Sporangia Slime – Stream along as a plasmodium = multinucleate mass of cytoplasm (slime) with no cell wall heterotrophs Form called feeding phase – Ingests bacteria & other organic material – Plasmodium (malaria) 28.9: Supergroup: Opisthokonta From the cladogram, are animals more closely related to fungi than to Land plants? Are fungi more closely related to Land plants than to animals? Suergroup: Opisthokanta Choanoflagellates – Unicellular organisms – a structure is exactly matched in sponges, which are animals – Fungi & animal share common ancestor Excavata Protista SAR Euglenazoa Rhizaria Radilorarius Foramifera Euglenids Kinetoplastids (Euglena) (Trypanasoma) Amoebazoa Opisthokonta SAR Alveolata Stramenopila Dinoflagellates Ciliates Apicomplexans Brown Algae Diatoms (Paramecium) (Plasmodium) Archaeplastida Rodophyta Chlorophyta Charophyta Land Plants Green: Super group Red: Group/Phylum Black: Sub-groups Protista Cladogram Protista SAR Archaeplastida SAR Amoebezoa Opisthokonta Excavata Rhizaria Euglenozoa Parabasalid Foraminifera Radiolaria Chloro phyta Rhodophyta Alveolata Stramenopila Euglenids Kinetoplastida Brown Algae Diatoms (Phylum (Euglena) ( Trypanasoma) Chrysophyta) Dinoflagellata Apicomplexans Ciliata ( Plasmodium) (Paramecium; Ceratium; Stentor; Blespharisma) Green: Super groups Red: Groups Black: Sub- groups ta 28.9 Paper Summary Last day to approve is Friday October 25, 2024. On Friday I will be approving your manuscripts that you will use to prepare your abstracts/summaries. Your manuscripts must be a primary research article, as we had discussed in class. Therefore, it must be original research by the person(s) who actually conducted the research. As such, it must include sections describing the methods used, results found, and discussion of their meaning. Please have your titles, year and author ready to email to me once I approve the article. Shotel 2024 Beginning Wednesday November 22, 2024, each group of two (2) students will make a 5-8 minute presentation on some scientific topic of interest to him/her. This can take the form of live material, pictures or your video. The video must be your own You will be presenting by group: – Please begin to choose your group member and your topic – Group and Topics due on Monday October 28, 2024 This will be Quiz 9 You will need to clear your presentation topic with instructor Lecture and Lab Requirements LECTURE LAB Abstract on a scientific Lab Report on Competition manuscript-primary literature – Due March 16, 2023 Papers due March 15, 2023 – Must use Writing Center Assignment due April 12, 2023 Project Research – Questions you would like to ask – Must use Writing Center Feb 16, 2023 – Project Titles and Hypotheses- March 2, 2023 – List of Materials- March 16, 2023 – Oral Presentation – April 27, 2023 Quiz 4 Excavata Protista Rhizaria Euglenazoa Radilorarius Foramifera Euglenids Kinetoplastids (Euglena) (Trypanasoma) Amoebazoa Opisthokonta Chromalveolata Alveolata Stramenopila Dinoflagellates Ciliates Apicomplexans Brown Algae Diatoms (Paramecium) (Plasmodium) Archaeplastida Rodophyta Chlorophyta Charophyta Land Plants Green: Super group Red: Group/Phylum Black: Sub-groups Protista Cladogram Protista Rhizaria Archaeplastida Chromalveolata Amoebezoa Opisthokonta Excavata Euglenozoa Parabasalid Foraminifera Radiolaria Chloro phyta Rhodophyta Alveolata Stramenopila Euglenids Kinetoplastida Brown Algae Diatoms (Phylum (Euglena) ( Trypanasoma) Chrysophyta) Dinoflagellata Apicomplexans Ciliata ( Plasmodium) (Paramecium; Ceratium; Stentor; Blespharisma) Green: Super groups Red: Groups Black: Sub- groups 28.4: Super group: Chromalveolata Supergroup consisting of two branches: Chromalveolata Alveolata Stramenopila Dinoflagellates Ciliates Apicomplexans Brown Algae Diatoms (Paramecium, (Plasmodium) Ceratium; Stentor; Blespharisma) STOP Review Three methods have been used to try to eradicate malaria: – One is to eliminate the mosquito vectors of the parasite, – a second is to kill the parasites after they entered the human body, and – the third is to develop a vaccine against the parasite, allowing the human immune system to provide protection from the disease. – Which do you suppose is the most promising in the long run? Why? Think about both the biology of the disease and the efficacy of carrying out each of the methods on a large scale. Review Development of a vaccine, though challenging, will be the most promising in the long run. – It is difficult to eradicate all the mosquito vectors, and many eradication methods can be harmful to the environment. – Treatments to kill the parasites are also difficult because the parasite is likely to become resistant to each new poison or drug. A vaccine would provide long-term protection without the need to use harmful pesticides or drugs for which drug resistance is a real possibility. Protista Cladogram Protista Rhizaria Archaeplastida Chromalveolata Amoebezoa Opisthokonta Excavata Euglenozoa Radiolaria Foraminifera Chlorophyta Land Plants Stramenopila Alveolata Euglenids Kinetoplastida Rhodophyta Charophyta Brown Algae Diatoms (Phylum (Euglena) (Trypanasoma) Chrysophyta) Dinoflagellata Apicomplexans Ciliata (Plasmodium) (Paramecium) Green: Super groups Red: Groups Black: Sub-groups Lab: Procedure: Protists Supergroup Amoebozoa: Amoeba proteus (slide) x100 Supergroup Excavata: Supergroup Excavata: Group Euglenozoa: Euglena (slide) Group Parabasalids: Termite flagellates (slide) Supergroup Excavata: Group Parabasalids: Leishmania donovani (slide) x400 x200 Look for flagella x400