Kingdom Protista

Kingdom protistana Characteristics Mostly uni prison cubicleular, eukaryotic cells Re start out asexu whollyy or sexually by conjugation Exhibit all leash modes of nutrition Photosynthesis Ingestion Absorption Ultimately spawned all multicellular kingdoms real diverse kingdom Difficult for taxonomists to agree on classification divers(prenominal) Modes of Nutrition Use diverse modes of nutrition Ingest food kotow nutrients from surroundings Photosynthesis Protists that ingest food are typically p chromaticators Use extensions of cell membrane called psuedopods to surround and absorb prey item Diverse Modes of NutritionProtists that reap nutrients directly from the surrounding environment can be Free-living types in the alter that decompose organic dead head quick studys that hold out wrong the bodies of another(prenominal) organisms, sometimes harming the host Diverse Modes of Nutrition somewhat protistans aim photosynthetic organelles called chloroplasts Photosynthet ic protists are abundant in oceans, lakes, and ponds Free natation inversely beneficial associations with other organisms solar energy captu rubor by the protist is use by host, which shelters and protects the protist Diverse Modes of NutritionPhotosynthetic protists are collectively know as algae Single-celled, non-photosynthetic protists are collectively cognise as phylum Protozoa Diverse Modes of Reproduction Most protists reproduce asexually by mitotic cell division Some also reproduce sexually 2 individuals impart genetic material to an offspring that is genetically different from either elicit Occurs during certain time of year or circumstances (e. g. a displace environment or a food shortage) Protist Reproduction apomictic Sexual (a) (b) Effects on HumansPositive impact ecological role of photosynthetic leatherneck protists (algae) capture solar energy and make it available to the other organisms in the ecosystem release oxygen gas Negative impact some(prenominal) human and plant diseases are caused by parasitic protists major(ip) Groups of Protists Protist classification is in transition Genetic comparison reveals evolutionary level of organisms Genetic, instead of physical features now separate protist species into different lineages Some physically dis exchangeable species are now placed in a common lineage The Excovates Lack mitochondriaTwo major groups Diplomonads have two nuclei and hightail it about by means of multiple flagella Parabasalids live inside animals Parabasalids Mutually beneficial relationships with other species Parabasalid inhabits gut of termite Termite delivers food to parabasalid, which digests and releases nutrients to termite Parabasalids Harms host species Trichomonas vaginalis causes the sexually transmitted disease trichomoniasis Trichomonas inhabits urinary and reproductive tracts, employ flagella to move done them Causes vaginal itching and discharge in females The EuglenozoansHave typical mitochondria T wo major groups Euglenids Kinetoplastids Euglenids Single-celled, spanking-water protists Lack a rigid outer concealment Best known example is Euglena Moves by whipping single bane Photosynthetic Some euglenids photosynthetic, others absorb/engulf food Euglenids Photoreceptor (eyespot) found in some euglenoids Provides for a way to sense location of clea bolshy microbe Useful for photosynthetic euglenoids in maximizing photosynthesis Euglena a Representative euglenophyte Flagellum Eye Spot Contractile Vacuole Stored Food Nucleus nucleole Chloroplasts Kinetoplastids exclusively species have one or more flagella Can be used for propulsion, sensing, or food gathering Many are free-living in soil and water Kinetoplastids Some species live in a dependent mutualistic association within another organism Some species digest cellulose in termite guts Trypanosomes live within tsetse flies and cause African sleeping sickness in fly-bitten mammals Trypanosomes infect the blood causatio n African sleeping sickness Trypanosomes in Blood The Stramenophiles Have fine, hair-like projections on flagella Mostly single-celled but some multicellularSome are photosynthetic species Major stramenophile groups pissing molds Diatoms embrown algae Water Molds Also known as oomycetes Long filaments aggregated into cottony tufts Many are soil and water-based decomposers Water Molds Profound economic impacts caused by water molds Late chevvy attacks potato plants (caused Irish potato famine in 1845) One species causes downy mildew (nearly destroyed French wine industry in 1870s) A Parasitic Water Mold Downy mildew on grapes Diatoms comprise in twain fresh and salt water Photosynthetic stir shells of silica that fit togetherDiatomaceous earth is cleaves of diatom shells (mined and used as an abrasive) Diatoms Part of go phytoplankton community Important in absorbing CO 2 and producing O 2 Phytoplankton per category 70% of all photosynthesis Diatoms are important as food in m arine food webs Herbivorous organisms graze on these pastures of the sea Brown Algae Form multicellular aggregates (seaweeds) Superficially alike(p) but not closely related to plants Contain brownish-yellow and jet (chlorophyll) pigments producing brown/olive appearance Brown Algae Nearly all marine build along rocky shores of temperature oceans Includes giant kelp Several species use gas-filled floats to support dust Giant kelp forests provide food and shelter for sea animals Diverse Brown Algae Fucus sp. Giant Kelp The Alveolates Single-celled protists with small cavities beneath cell near (alveoli) Comprise a distinct lineage Nutritional modes include photosynthetic, parasitic, and wolfish The Alveolates Major alveolate groups Dinoflagellates Apicomplexans Ciliates Dinoflagellates Mostly photosynthetic Two whip-like flagellaMost species live in salt water Some species bioluminescent Certain specialized dinoflagellates live within coral, clam, and other protistan hosts Cell w all resembles armored plates Dinoflagellates & release Tide Red Tide Dinoflagellates Nutrient-rich water causes population explosion called red tides Substantial fish kills result from oxygen depletion and clogged gills Oysters, mussels, and clams put on from large food supply but may accumulate spunk poison Lethal paralytic shellfish drunkenness in manhood may result from eating these shellfishApicomplexans Also known as sporozoans all members are parasitic Form infectious spores Spores transmitted between hosts by food, water, or insect bites Apicomplexans Complex life cycle (e. g. Plasmodium- malarial parasite) Parasite passed to human by Anopheles mosquito Plasmodium develops in liver, makes spores in red blood cells (causing fever upon release) New mosquitoes acquire parasite while nutrition on blood Plasmodium quickly evolves resistance to drugs Ciliates Inhabits both fresh and salt waterHighly complex unicellular organization Specialized organelles Cilia that propel ce lls by dint of water at 1 mm/s Ciliates Examples of ciliate complexness Paramecium (contractile vacuoles, nervous system) Didinium (predator of other microbes) Paramecium has vacuoles and cilia The Complexity of Ciliates Macronucleus Micronucleus Food Vacuole vocal Groove Contractile Vacuole Cilia Food Vacuole bodying The Cercozoans Cercozoans have thin, threadlike psuedopods, which extend through hard shells in some species Cercozoans includeForaminifera Radiolarians The Cercozoans Foraminiferans produce elaborate calcium change shells with holes Deposits of fossilized foraminiferans form chalk Radiolarians have silica shells Heliozoans The Amoebozoans Amoebozoans move by extending finger-shaped pseudopods, also used for feeding Inhabit aquatic and terrestrial environments broadly speaking do not have shells The major groups of amoebozoans are Amoebas bemire molds The Amoebozoans Amoebas Found in freshwater lakes and ponds Predators that stalk and engulf preyOne species caus es amoebic dysentery The Amoebas The Slime Molds intelligibly unique lineage among protists Physical form blurs distinction between a colony versus an individual The Slime Molds Two-phase life cycle Mobile feeding stage Stationary, reproductive stage forming a fruit body Two main types Acellular Cellular Acellular Slime Molds Also known as plasmodial slime molds Composed of a thinly spread cytoplasm with multiple diploid nuclei Plasmodial mass feeds on bacteria and organic matter by engulfing them Acellular Slime MoldsCan form bright yellow or orange masses Dry conditions or starvation stimulate fruit body formation Haploid spores produced Spores disperse and germinate into a rising plasmodium The Acellular Slime Mold Physarum (a) (b) Cellular Slime Molds hold up in soil as independent haploid cells Pseudopodia surround and engulf food (like bacteria) Cellular Slime Molds Food scarcity creates a pseudoplasmodium individual(a) cells release chemical signal if food is scarce Dense , slug-like aggregation of cells forms carrier bag crawls towards light, forms a fruiting body Haploid spores produced are dispersed to form new single-celled individuals The Life Cycle of a Cellular Slime Mold Single, amoeba-like cells emerge from spores, crawl, and feed. When food is scarce, cells aggregate into slug-like mass called pseudoplasmodium. Pseudoplasmodium migrates toward light, forms fruiting bodies produces spores. fruiting bodies spores nucleus The Red Algae Multicellular, photosynthetic seaweeds Pigments combined with chlorophyll produce bright red to black appearances Found exclusively in marine environmentsThe Red Algae Very common in deep, clear equatorial waters Red pigments absorb deeply penetrating blue-green light Can therefore live deeper than other seaweeds The Red Algae multifariousness of forms and uses Some species deposit calcium carbonate Some species harvested for food nil captured by red algae important in food durance Products extracted from r ed algae include Carrageenan (stabilizing agent) Agar (substrate for bacteria in petri dishes) The Red Algae Multicellular, photosynthetic seaweeds, ranging in color from bright red to nearly black Live in clear tropical oceansSome species deposit calcium carbonate, which contributes to the formation of reefs Red Algae The Green Algae All species photosynthetic Both multicellular and unicellular species Found in both freshwater and marine environments Some form long filamentous custody of cells (e. g. Spirogyra ) Spirogyra A Green Algae The Green Algae Some form colonies of clustered cells (e. g. Volvox ) Mostly microscopic forms but Ulva (sea lettuce) is a multicellular leaf-sized green algal seaweed The Green Algae Green algae are closely related to plantsThe earliest plants may have been similar to todays multicellular green algae Protists and Life devil dog phytoplankton 70% of all photosynthesis Diatoms abrasive products and oil reserves Sarcodines and limestone deposits Pro tists and disease Water molds downy mildew, late blight of potato Dinoflagellates and red tide, shellfish poisoning Zooflagellates African sleeping sickness, Giardia Sarcodines amoebic dysentery Sporozoans Plasmodium and malaria Giardia the Curse of Campers