Kingdom protista

1. Kingdom ProtistaKingdom Protista

2. 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

3. 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 organisms
Do 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

4. 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
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Paramecium
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5. Protists and FoodProtists and Food
Protists can get food many ways:Protists can get food many ways:
Can make own foodCan make own food
Can Can eateat other organisms other organisms
Can eat parts or products of other organismsCan eat parts or products of other organisms
Can eat Can eat remainsremains of other organisms of other organisms
Some use more than one way to get foodSome use more than one way to get food
Some Some produceproduce food—they use food—they use chloroplastschloroplasts
to produce food through photosynthesisto produce food through photosynthesis

6. Finding FoodFinding Food
HeterotrophHeterotroph: organism that cannot : organism that cannot
makemake own food own food
Some are Some are decomposersdecomposers—they get —they get
energy by breaking down dead energy by breaking down dead
organic matterorganic matter

7. 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

8. 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

9. 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 through
photosynthesisphotosynthesis
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

10. 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””

11. 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

12. 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

13. 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

14. 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

15. Brown algaeBrown algae
Most 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

16. 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

17. 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