Post on 22-May-2015
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Kingdom ProtistaKingdom Protista
General CharacteristicsGeneral Characteristics
Protists are very Protists are very diversediverse and have few and have few traits in commontraits in common
Most are single-celled organisms, but Most are single-celled organisms, but some are many cells, and others live in some are many cells, and others live in coloniescolonies
Some produce own Some produce own foodfood, others eat other , others eat other organisms or decaying matterorganisms or decaying matter
Some can control own Some can control own movementmovement, others , others cannotcannot
Characteristics that protists Characteristics that protists DODO share: share:Eukaryotic (have a nucleus), but are less Eukaryotic (have a nucleus), but are less
complex than other eukaryotic organismscomplex than other eukaryotic organismsDo not have specialized Do not have specialized tissuestissues
Members of the kingdom Protista are Members of the kingdom Protista are related more by how they related more by how they differdiffer from from members of other kingdoms than by how members of other kingdoms than by how they are similar to other protiststhey are similar to other protists
Protists have many Protists have many different shapesdifferent shapes
Most scientists Most scientists agree that fungi, agree that fungi, plants, and animals plants, and animals evolved from early evolved from early protistsprotists
zooflagellates
ulva
Paramecium
Pretzel slim
e m
old
Protists and FoodProtists and Food
Protists can get food many ways:Protists can get food many ways:Can make own foodCan make own foodCan Can eateat other organisms other organismsCan eat parts or products of other organismsCan eat parts or products of other organismsCan eat Can eat remainsremains of other organisms of other organismsSome use more than one way to get foodSome use more than one way to get foodSome Some produceproduce food—they use food—they use chloroplastschloroplasts
to produce food through photosynthesisto produce food through photosynthesis
Finding FoodFinding FoodHeterotrophHeterotroph: organism that cannot : organism that cannot
makemake own food own foodSome are Some are decomposersdecomposers—they get —they get
energy by breaking down dead energy by breaking down dead organic matterorganic matter
Asexual ReproductionAsexual Reproduction
Most protists Most protists reproduce reproduce asexuallyasexually
Offspring come from Offspring come from just just oneone parent parent
Binary fissionBinary fission: a : a single-celled protist single-celled protist dividesdivides into two cells into two cells
Each new cell is a Each new cell is a single-celled protistsingle-celled protist
Sexual ReproductionSexual Reproduction
Requires two Requires two parentsparents Paramecium Paramecium
sometimes reproduce sometimes reproduce sexually by a process sexually by a process called called conjugationconjugation
Kinds of ProtistsKinds of Protists AlgaeAlgae
All algae have the All algae have the greengreen pigment pigment chlorophyll, which is chlorophyll, which is used to make food used to make food through photosynthesisthrough photosynthesis
Almost all algae live in Almost all algae live in waterwater
Free-floating, single-Free-floating, single-celled algae are called celled algae are called phytoplanktonphytoplankton, which , which produce much of the produce much of the world’s world’s oxygenoxygen
AmoebasAmoebas Soft, jellylike Soft, jellylike
protozoansprotozoans Found in fresh and salt Found in fresh and salt
water, soil, and in water, soil, and in parasitesparasites
Move with Move with pseudopodia, which pseudopodia, which means “means “false feetfalse feet””
CiliatesCiliates Have hundreds of Have hundreds of ciliacilia——
tiny, hairlike structurestiny, hairlike structures Cilia Cilia movemove the protist the protist
forward by beating back forward by beating back and forth—sometimes up and forth—sometimes up to 60 times a second!to 60 times a second!
Cilia are also used for Cilia are also used for feedingfeeding—they move the —they move the food towards the protist’s food towards the protist’s food passagewayfood passageway
Best known of ciliates is Best known of ciliates is the Parameciumthe Paramecium
Spore-Forming ProtistsSpore-Forming Protists Many spore-forming Many spore-forming
protists are parasitesprotists are parasites They They absorbabsorb nutrients from nutrients from
their hoststheir hosts No cilia or flagella, cannot No cilia or flagella, cannot
movemove on their own on their own Have complicated life Have complicated life
cycles that usually cycles that usually includes two or more hostsincludes two or more hosts
Example: protist that Example: protist that causes malaria uses both causes malaria uses both mosquitoes and humans mosquitoes and humans as hostsas hosts
Slime MoldsSlime Molds Heterotrophic and can Heterotrophic and can
only move during certain only move during certain periods of life cycleperiods of life cycle
Look like Look like thinthin, colorful , colorful globs of slimeglobs of slime
Use pseudopodia to Use pseudopodia to movemove and eat fungi and and eat fungi and yeastyeast
When environmental When environmental conditions are stressful, conditions are stressful, slime molds grow slime molds grow stalksstalks with knobs, which contain with knobs, which contain sporesspores
Red AlgaeRed Algae Most of world’s Most of world’s
seaweedseaweed is red algae is red algae Most live in tropical Most live in tropical
oceansoceans Usually less than 1 m Usually less than 1 m
in lengthin length Contain chlorophyll, Contain chlorophyll,
but have but have redred pigmentpigment Red pigment allows Red pigment allows
them to absorb them to absorb light light that filters deep into that filters deep into oceanocean
Brown algaeBrown algaeMost seaweed in Most seaweed in coolcool
climates are brown climates are brown algaealgae
Attach to rocks or form Attach to rocks or form large floating beds in large floating beds in ocean watersocean waters
Have chlorophyll and Have chlorophyll and yellow-brown pigmentyellow-brown pigment
Many are very Many are very largelarge—up —up to 60 metersto 60 meters
Green algaeGreen algae Most diverse of protist Most diverse of protist producersproducers Green because Green because chlorophyllchlorophyll is main pigment is main pigment Most live in water or moist soilMost live in water or moist soil Others live in melting snow, on tree trunks, and Others live in melting snow, on tree trunks, and
inside other organismsinside other organisms
DiatomsDiatoms Single-celledSingle-celled Found in salt and fresh waterFound in salt and fresh water Get energy from Get energy from photosynthesisphotosynthesis Make up a large percentage of phytoplanktonMake up a large percentage of phytoplankton Cell walls contain a glasslike substance called Cell walls contain a glasslike substance called silicasilica