Ch.12 Eukaryotes PDF

Eukaryotes – Ch.12 o Classifying Eukaryotes – domains and kingdoms o Prokaryotic vs. Eukaryotic – key differences o Protista  protozoa amebas alveolates – ciliates, flagellates and dinoflagellates apicomplexans and trypanosomes  algae o Fungus – filamentous and yeast o Lichen...

Eukaryotes – Ch.12 o Classifying Eukaryotes – domains and kingdoms o Prokaryotic vs. Eukaryotic – key differences o Protista  protozoa amebas alveolates – ciliates, flagellates and dinoflagellates apicomplexans and trypanosomes  algae o Fungus – filamentous and yeast o Lichen and Mycorrhizae Objectives: Describe the four eukaryotic kingdoms as it relates to the evolutionary tree of life Differentiate the processes of asexual (vegetative) reproduction and sexual reproduction. For the following - distinguish key traits and describe their role in the environment and human disease - fungi, algae, amebas, ciliates, and trypanosomes. Distinguish between microbial and invertebrate parasites. Provide an example and describe the infectious cycle of a eukaryotic parasite.  Ch.12 - Eukaryotes diatom protozoa Divided into 4 kingdoms: type of algae ameba eating paramecium 1. protista algae protozoa 2. plants 3. fungi 4. animals plant: corpse flower fungus: fungal fruiting body animal cell world’s largest and stinkiest flower morula: human embryonic stem cells Tree of Life: bacteria – 1st living organism… ALL life ultimately evolved from bacteria! protist – the evolutionary split from prokaryotes… the 1st eukaryotes 2 groups: protozoa and algae  Eukaryotes – Ch.12 o Classifying Eukaryotes – domains and kingdoms o Prokaryotic vs. Eukaryotic – key differences o Protista  protozoa amebas alveolates – ciliates, flagellates and dinoflagellates apicomplexans and trypanosomes  algae o Fungus – filamentous and yeast o Lichen and Mycorrhizae  prokaryotic vs. eukaryotic cell structure comparison Prokaryotes vs. Eukaryotes 2 cell types: prokaryotic and eukaryotic o prokaryote bacteria and archaea from Greek word for pre-nucleus o eukaryote Prokaryotic: Eukaryotic: smaller larger protist, fungi, plants, and animals simpler complex from Greek words for true nucleus unicellular uni or multicellular no nucleus or organelles nucleus and organelles binary fission mitosis and meiosis  Think… Pair… Share o Can you draw the evolutionary tree of life? Indicate Domains and Kingdoms o What are the two types of cells in life? What are 4 major differences between the two? Which cell type are each of the different domains/kingdoms of life? Prokaryotic vs. Eukaryotic Cells eukaryotic cell… o can you describe the structure and function of important eukaryotic organelles? nucleus mitochondria golgi complex rough ER chloroplast smoot ER lysosome plasma membrane flagella eukaryotic Cell  Prokaryotic vs. Eukaryotic - Important Differences bacteria flagella eukaryotic flagella composed of flagellin protein subunits long “tail-like” microtubule extension of cell microtubules composed of tubulin protein subunits anchored to and external to plasma membrane membrane-bound cylinders cell movement - rotate (360⁰) in clockwise or 9 + 2 pattern of microtubules counterclockwise motion internal to plasma membrane “run” and “tumble” cell movement cell movement - rotate back and forth - “side to side” in “whip-like” motion  bacteria fimbriae and pili eukaryotic cilia Fimbriae and Pili composed of pilin protein subunits short “hair-like” microtubule extension of cell like flagella… anchored to and external to plasma membrane o microtubule cylinders of tubulin subunits Fimbriae - “hairlike” appendages for attachment o 9 + 2 pattern of microtubules Pili - “tube” filament for conjugation (cell-cell internal to plasma membrane plasmid transfer) or slow movement – “twitching” unicellular protozoa algae: o cell movement - rotate back and forth - “side to side” in “whip-like” motion o eating - direct current toward mouth multicellular organisms: move fluid along surface – lining of lungs and digestive tract bacterial pili with conjugation pili fimbriae and vesicles budding from cell’s membrane  Cell Division Differences prokaryotes: binary fission o bacteria are haploid (n) – 1 circular chromosome o asexual reproduction – 2 genetically identical daughter cells (clones) o cell division = binary fission - copy chromosome and divide replicate DNA chromosomes migrate to opposite ends plasma membrane “pinches in” in center of cell new cell wall forms cell divides into two daughter cell clones binary fission in Staphylococcus aureus  eukaryotic cell divisions: mitosis and meiosis eukaryotes alternate between haploid (n) and diploid (2n) Prokaryotic vs. Eukaryotic: multiple linear chromosomes Cell Division Differences Mitosis – asexual - 2 genetically identical cells Meiosis – sexual - 4 genetically unique cells Mitosis (haploid or diploid) 1. Prophase asexual reproduction produces 2 genetically identical cells (clones) 2. Metaphase diploid cell (2n) - creates two diploid cells (2n→2n) 3. Anaphase haploid cell (n) creates two haploid cells (n→n) like binary fission but multiple linear chromosomes 4. Telophase replicate chromosomes spindle fibers to separate chromosomes 5. Cytokinesis steps – P, M, A, T, C Meiosis (diploid only) o sexual reproduction 1. Prophase-I crossover recombination o produces 4 genetically unique haploid cells o 2 haploid cells/nuclei merge (n+n) – create diploid 1. Metaphase-I independent assortment cell (2n) unique cells o DNA of 2 cells combine – genetic recombination! 3. Anaphase -II crossover (prophase-I) independent assortment (metaphase-I) 4. Telophase/Cytokinesis-II o 2 rounds of cell division 1. Meiosis-II meiosis I (1 cell → 2 cells) - P,M,A,T,C-1 meiosis II (2 cells → 4 cells) - P,M,A,T,C-2 eukaryotic sexual reproduction (meiosis) - immensely important for evolution! o allowed for greater genetic variability o evolution and life’s diversity “took off”!  Meiosis: Mitosis: sexual asexual crossover unique to meiosis NO crossover or independent assortment independent assortment unique to meiosis 4 genetically 2 genetically unique cells identical cells  Eukaryotes – Ch.12 o Classifying Eukaryotes – domains and kingdoms o Prokaryotic vs. Eukaryotic – key differences o Protista  protozoa amebas alveolates – ciliates, flagellates and dinoflagellates apicomplexans and trypanosomes  algae o Fungus – filamentous and yeast o Lichen and Mycorrhizae  protozoa - ameba Kingdom Protista - 1st eukaryote! eating paramecium protozoa - stentor (ciliate) o evolved from bacteria o asexual and sexual reproduction! two “main groups” of protist: 1. protozoa – gave rise to fungus and animals amebas, ciliates, apicomplexins 2. algae – gave rise to plants includes diatoms and dinoflaggelates algae - volvox algae - diatom o most uni-cellular; some colonial or multi-cellular o most structurally and functionally diverse group of eukaryotes o autotrophs (algae); heterotrophs (protozoa) or mixotrophs (dinoflagellates) o live in moist environments o some pathogenic: disease causing  Protozoa: “proto” first; “zoa” animal Gave rise to animals! Incredibly diverse! Protozoan Characteristics: o unicellular - exception: Plasmodium Slime Mold o most heterotrophs; some mixotrophs o motility - flagella(s), cilia or cytoplasmic flow o most have thin outer protective protein coat - pellicle o asexual or sexual reproduction o sexual reproduction! Protozoan “Conjugation”  Protozoan Characteristics: o sexual reproduction – genetically unique cells! conjugation - different from bacteria conjugation cells create haploid “micronuclei” two cells fuse - exchange haploid “micronuclei” haploid nucleus fuses with haploid nucleus of receiving cell Protozoan “Conjugation”  Eukaryotes – Ch.12 o Classifying Eukaryotes – domains and kingdoms o Prokaryotic vs. Eukaryotic – key differences o Protista  protozoa amebas alveolates – ciliates, flagellates and dinoflagellates apicomplexans and trypanosomes  algae o Fungus – filamentous and yeast o Lichen and Mycorrhizae  Amebas: use “pseudopod” or “false foot” for locomotion extends cytoplasmic “extensions” (“foot”) cell body cytoplasm flows in that direction 2 major groups: lobed amebas – “bulky” cytoplasmic pseudopods filamentous ameba filamentous amebas – thin “needlelike” pseudopods pseudopodium (false foot) lobed ameba eating Paramecium  pathogenic amebas Entamoeba hystolytica Naegleria fowleria cause amebic dysentery (bloody diarrhea) cause brain-eating ameba disease… ingest red blood cells damage digestive tissues amebic meningoencephalitis fecal-oral transmission warmer freshwater only trophozoite - active-eating stage enters nasal and olfactory tissue cist –dormant stage crosses the blood brain barrier (BBB) Entamoeba hystolytica consumes brain tissue. > 98% fatal amebic dysentery via fecal-oral transmission Acanthamoeba corneal infection (keratitis) dirty contacts / eye-drops  Eukaryotes – Ch.12 o Classifying Eukaryotes – domains and kingdoms o Prokaryotic vs. Eukaryotic – key differences o Protista  protozoa amebas alveolates – ciliates, flagellates and dinoflagellates apicomplexans and trypanosomes  algae o Fungus – filamentous and yeast o Lichen and Mycorrhizae  Alveolates - named for “flattened vacuoles” in outer cortex called alveoli stiff material - protein, polysaccharide or mineral ALL extracellular and use cilia or flagella Ciliates: named for their use of cilia to move and feed o ALL unicellular Paramecium o most non-pathogenic o most heterotrophs; some mixotrophs o motility and feeding - cilia composed of microtubules o pellicle: “thin” protective extracellular protein coat susceptible to osmotic lysis contractile vesical – “pumps out” intracellular water o cytosome (mouth) - eat by waving cilia toward cytosome o vacuoles: organelle where digestion takes place o anal pore (butt) – elimination of waste Didinium engulfing o eye spot - senses light direction Paramecium mixotrophs only – photosynthetic  flagellates - named for their use of flagella to move and feed o ALL unicellular; hetertrophs o many intestinal pathogens (parasitic) o anaerobic – noted for their lack of mitochondria! o motility - flagella composed of microtubules Giardia o many have “active” and “dormant” stages intestinalis trophozoite – “active” free-swimming feeding stage cyst – dormant stage  tough, protective protein capsule  enables transfer between hosts Giardia lamblia Trichomonas vaginalis cause Trichomoniasis toxins and metabolic byproducts effect cells of intestine STD - human genital tract only know reservoir affecting ability to absorb H2O and fats toxins / metabolic byproducts stress cells killing them causing extreme diarrhea ingests cell fragments after cell death  dinoflagellates (phytoplankton) the symbiotic side…. ALL uni-cellular o Symbiosis - corals, anemones, sponges called phytoplankton provide glucose in exchange for safe o producers – base of food chain habitat auto, hetero, or mixotrophs o zooxanthellae – coral endosymbiont cellulose cell wall; rigid structure temp/pH sensitive – climate change increasing ocean temp/acidity. alveolar plate – extracellular protein layer; armor-plated appearance coral bleaching – expulsion of zooxanthellae bi-flagellated - 2 flagella leads to coral damage and/or death toxic “blooms” “blooms” – often water pollution indicator the pathogenic side…. o some produce neurotoxins most inhibit breathing o toxin - paralytic shellfish poisoning (PSP) RED TIDE – Alexandrium “bloom” gives deep red color ingesting infested shellfish dinoflaggelates dinoflagellate ‘bloom” induced red tide  Eukaryotes – Ch.12 o Classifying Eukaryotes – domains and kingdoms o Prokaryotic vs. Eukaryotic – key differences o Protista  protozoa amebas alveolates – ciliates, flagellates and dinoflagellates apicomplexans and trypanosomes  algae o Fungus – filamentous and yeast o Lichen and Mycorrhizae  apicomplexins: intracellular parasites named for “apical complex” used to enter cells o ALL unicellular o all heterotrophs o NO flagella or cilia o cortex: protective protein coat (analogous to pellicle) susceptible to osmotic lysis contractile vesical – “pumps out” intracellular water o apicomplexan caused diseases… malaria – Plasmodium falciparum or Plasmodium vivax toxoplasmosis – Toxoplasma gondii babesiosis - Babesia microti malaria - Plasmodium falciparum or Plasmodium malarie intracellular blood parasite P. falciparum primary host / vector = mosquito A – infecting RBC’s sporozoites infect liver cells: transform to merozoites B – entering an RBC infect/lyse RBC’s – released into bloodstream violent chills and cyclic fever toxoplasmosis - Toxoplasma gondii intracellular parasite – spores enter via ingestion 30% humans infected! (most asymptomatic!) T. gondii can infect ALL nucleated cells – muscles / CNS cysts can sometimes infect brain primary host = cat / cyst transmitted via cat feces enter intestinal cells / multiply / lyse cell - spread chagas (American trypanosomiasis) - Trypanosoma cruzi intracellular parasite – vector = Reduvilid “kissing bug” Chagas enters via bug feces by scratching or rubbing bite site disease most minor infection = fever and tissue edema chronic (25%) = liver, spleen, CNS, heart infections A=T. cruzi; B=“kissing bug”; C=eye edema (Romana sign)  Leishmaniasis (black fever) African trypanosomiasis – African Sleeping Sickness o cutaneous – Leishmania tropica o Trypanosoma bruccei o visceral - Leishmania donovani intracellular blood parasite - infect RBC’s and CNS intracellular blood parasite - infect RBC’s and CNS primary host / vector = tsetse fly primary host / vector = sand fly produce toxin crosses BBB - extreme drowsiness cutaneous–darkening of skin / fever (black fever) evade immune system – changes surface proteins visceral – die within months if untreated known as “antigenic variation” o hemorrhage, anemia, enlarged spleen / liver, each generation “different” protein! septicemia, secondary infections immune system can’t develop accurate antibodies o infect macrophages – spread throughout body extreme fever / drowsiness - death if untreated Leishmania donovani A – sand fly (vector) B – Leishmania donovani Trypanosoma C – visceral Leishmaniasis bruccei hepatosplenomegaly tape indicates infected areas of liver (bottom left) and spleen (bottom right)  Protozoan’s Great Diversity! Amoeba Strombidium pseudopodium (foot) Tetrahymena Euglena Amoeba eating Paramecium Didinium engulfing Paramecium Oxytricha  Eukaryotes – Ch.12 o Classifying Eukaryotes – domains and kingdoms o Prokaryotic vs. Eukaryotic – key differences o Protista  protozoa amebas alveolates – ciliates, flagellates and dinoflagellates apicomplexans and trypanosomes  algae o Fungus – filamentous and yeast o Lichen and Mycorrhizae algae: photosynthetic protist …you remember photosynthesis! o makes glucose from carbon dioxide, water and light CO2 + H2O + light = glucose + O2 o produces glucose sugar for food chain o produces oxygen gas (O2) as a biproduct algae characteristics: gave rise to plants provides ≥50% worlds O2 uni-cellular; colonial or multi-cellular; ALL aquatic cellulose or silicon (diatoms) cell walls many have flagella 4 groups (green, golden, brown and red) – each absorbing different wavelengths of light can create “gigantic blooms” – some are toxic  algae types: classified by photosynthetic wavelength o absorption wavelength of photosynthetic pigments o deeper algae higher-energy wavelength absorbed algae type by depth: o surface - green (uni/multi-cell) o ~20 ft. – golden (uni-cell) diatoms and dinoflagellates o ~100 ft. - brown (multi-cell; large) o >150 ft. - red (multi-cell) photosynthetic pigments: o chlorophyll’s A and B - reflect green o carotenoids - reflect orange o xanthophyls - reflect yellow  green algae brown algae red algae uni-cell, colonial or multi-cell ALL multi-cellular ALL multi-cellular non-toxic largest and most complex algae deepest living algae (to 250ft!) shallow depth – water surface non-toxic absorb high energy blue light named for chloroplast medium depth non-toxic o chlorophyll a and b - like plants! cellulose cell wall - like plants! cellulose cell wall - like plants! cellulose cell wall - like plants! kelp or giant “seaweed” Agar – indigestible polysaccharide store starch - like plants! algin – edible polysaccharide o for culturing microorganisms gave rise to plants o used as “thickener” in foods many edible many edible  golden algae the pathogenic side…. diatoms and dinoflagellates o diatoms - demoic acid toxicosis yellow color from carotenoid’s and xanthophyll's o amnesic shellfish poisoning (ASP) uni-cellular; some colonial ingesting infested crabs toxic “blooms” diarrhea/memory loss >24hrs; ≥4% fatality rate killed 1000’s marine birds and sea lions ALL photosynthetic; o dinoflagellates - mixotrophs 2015 – closed crab season diatoms uni-cellular; some filamentous non-flagellated silica cell walls! removes CO2 from atmosphere o after “pop. boom” – dead diatoms fall to ocean floor o bringing CO2 with them diatomaceous earth o fossilized diatom cell walls - natural insect pesticide  SiO2 dries out exoskeleton o “diatom mine” – old diatom sediments toxic “blooms”  Protist: Biomass of photosynthetic protists is declining as sea temperatures increase  Eukaryotes – Ch.12 o Classifying Eukaryotes – domains and kingdoms o Prokaryotic vs. Eukaryotic – key differences o Protista  protozoa amebas alveolates – ciliates, flagellates and dinoflagellates apicomplexans and trypanosomes  algae o Fungus – filamentous and yeast o Lichen and Mycorrhizae  Fungus Favolaschia calocera - called the Orange Pore Fungus AKA….“waffle on a stick” Amanita muscaria What is a Fungus?  Fungus o multicellular organism that produce “fruiting bodies” called mushrooms exceptions: YEAST and Chitrids (aquatic) – unicellular multicellular! protists and “early evolving” fungi are limit of single-cell life o mushroom releases spores that germinate to produce new fungus spore – “primitive seed”  Fungus evolved from Protist’s o humans and fungi evolved from a common ancestor: protozoa! 0 fungus more similar to animal than it is to a plant!  Fungus o heterotroph: consumes organic matter to live fungus consume just about anything: insects, food, wood, rock, YOU!!! insects/animals – “parasite” rock – “corrosive” plants – “parasite” Fungi - digest food externally secrete digestive exoenzymes that break down compounds for food when molecules small enough they are taken in by fungus  5 Fungi Characteristics: 1. fungi are multicellular yeast and chitrids are exception 2. fungi made of tube like structures called hyphae 3. hyphae make branching webs called mycelium 4. obtain nutrition by dissolving their food externally 5. sessile: fixed in one spot, but hyphae grow  Fungi’s Roll in Nature o can cause “lots o’ trouble” crop/tree infections skin afflictions - athletes foot, jock itch and ringworm bread molds toenail / fingernail infections food spoilage mildew and dry rot  Fungi’s Roll in Nature… however….can’t live without em’!!! antibiotics: source of penicillin and others organ transplants: immune suppressing molecules / drugs cholesterol lowering drugs yeast - fermenting of beer / “leavening” of bread o most important: major decomposers of world – recycling organic compounds breaking down material so atoms can be re-cycled for others to use Penicillin sensitive bacterial infection Before/after antibiotic treatment Penicillin  Fungi Structure Mushroom made of Hyphae o hyphae – tube like structures made of a thin line of cells o mycelium – branching web of hyphae o fruiting body or sporangia – mushroom reproductive structure - releases spores septum o hyphae – grow quickly from the tip o septum – separates individual cells porous - free flow of cytoplasm and nutrients between cells rapid flow of nutrients to tip of hyphae  Mushroom – made of hyphae/ mycelium gills - “accordion” like folds in underside of cap each gill a collection of hyphae basidium - reproductive structure within gills located at tip of gills produces reproductive spore cells spores are ejected from basidium dispersed by wind o 10 million spores ejected each hour from underside of mushroom cap!!!!!!!! Not all Fungi have Mushrooms… Bread Mold Yeast and Molds: fruiting bodies - reproductive structures topped with spores fruiting bodies look like tiny “lollipops”  Spores o haploid reproductive cell that develops into new organism without fusion with another cell two hyphae types: after germination only hyphae of opposite types can fuse to create spores similar to male/female sex cells fruiting body - bread mold  Yeast: single-celled fungi Yeast cells budding o belong to all phyla EXCEPT Chytrids o not a taxonomic category or a “specific form” of fungi o most aquatic o reproduction - reproduce by budding cell does NOT split down middle daughter cell produced as outgrowth of parent cell o makes bread rise – CO2 released as by-product of metabolism as it feeds o ferments bear/wine – alcohol (C-OH) released as byproduct of metabolism  Ch.12 – Eukaryotes o Classifying Eukaryotes – 4 kingdoms o Protists Algae Protozoa o Fungus o Lichen and Mycorrhizae o Helminths  Fungal Symbiotic Relationships o Lichen and Mycorrhizae 3 Ways Fungus obtain Nutrition 1. Parasite: gets nutrition from living organism 2. Saprophyte: extracts nutrients from dead organic matter 3. Mutualism: cooperative mutualism with other organisms live together and both parties benefit parasite saprophyte mutualism  Lichen: fungus and photosynthetic algae or bacteria living together o Fungus gets nutrients from algae/bacteria o Algae / bacteria get H2O, CO2, minerals and protection Why are Lichen so colorful? Make bright pigments - screen out harsh sunlight for algae/bacteria Lichens can live for THOUSANDS of years!!!! Lichen Structure - like a “sandwich” o Upper layer – dense hyphae o Middle layer – less dense hyphae and algae or bacteria o Bottom – dense hyphae sprouts hyphae “extensions” downward into material it’s living on  Mycorrhizae: fungus and plant roots living together o one of oldest symbiotic relationships in nature; 460 million years!!! o fungus get nutrients from plant root carbohydrates from photosynthesis o plants get H2O, CO2 and minerals from fungi phosphorus, nitrogen o fungal hyphae grow into or wrap around root Mycorrhizae