Kingdom ProtistaKingdom Protista

If you look at a drop of pond water If you look at a drop of pond water under a microscope, all the "little under a microscope, all the "little creatures" you see swimming around creatures" you see swimming around areare protistsprotists..

All protists have a nucleus and are All protists have a nucleus and are thereforetherefore eukaryoticeukaryotic. .

Protists are either plant-like, animal-like or Protists are either plant-like, animal-like or fungus-like.fungus-like.

Plant-like protists are Plant-like protists are autotrophsautotrophs – – they contain chloroplasts and make they contain chloroplasts and make their own food.their own food.

Animal-like and fungus-like protists Animal-like and fungus-like protists and areand are heterotrophsheterotrophs..

Why are Protists important?Why are Protists important?

They:They: provide food and energy for pond provide food and energy for pond

food chainsfood chains support the fish and animal life in support the fish and animal life in

and around the pond. and around the pond.

ProtozoansProtozoans are animal-like protistsare animal-like protists ((heterotrophsheterotrophs)) grouped according to grouped according to how they move.how they move.

The wordThe word protozoaprotozoa means "little means "little animal." They are so named because animal." They are so named because many species behave like tiny many species behave like tiny animals—specifically, they hunt and animals—specifically, they hunt and gather other microbes as food.gather other microbes as food.

All protozoa digest their food in All protozoa digest their food in stomach-like compartments called stomach-like compartments called vacuoles <vacuoles <vac-you-ohlsvac-you-ohls>>.. As they As they chow down, they make and give off chow down, they make and give off nitrogen, which is an element that nitrogen, which is an element that plants and other higher creatures can plants and other higher creatures can use. use.

they make and give off nitrogenthey make and give off nitrogen Protozoa range in size from 1/5,000 to Protozoa range in size from 1/5,000 to

1/50 of an inch (5 to 500 µm) in 1/50 of an inch (5 to 500 µm) in diameter. They can be classified into diameter. They can be classified into three general groups based on how three general groups based on how they move.they move.

4 types of Protozoans4 types of Protozoans

a)a) Move by ciliaMove by cilia

b)b) Move by “false-feet” (psuedopod)Move by “false-feet” (psuedopod)

c)c) Move by FlagellaMove by Flagella

d)d) Don’t move (parasites)Don’t move (parasites)

The first group is the phylum The first group is the phylum RhizopodaRhizopoda. . These are These are amoebaeamoebae < <ah-me-beeah-me-bee>, which can >, which can be subdivided into the testate amoebae, be subdivided into the testate amoebae, which have a shell-like covering, and the which have a shell-like covering, and the naked amoebae, which don't have this naked amoebae, which don't have this covering.covering.

Amoebae ooze along by means of Amoebae ooze along by means of pseudopodiapseudopodia (false feet) engulfing food as (false feet) engulfing food as they go.they go.

Amoebae live in water or moist Amoebae live in water or moist places.places.

They have a cell membrane but They have a cell membrane but no cell wall.no cell wall.

they have fluid cell membranes or they have fluid cell membranes or coverings that they can stretch out, coverings that they can stretch out, bend and curve.bend and curve.

The second group is theThe second group is the Flagellates Flagellates <<flah-geh-letsflah-geh-lets>, of the phylum >, of the phylum ZoomastiginaZoomastigina. Flagellates are . Flagellates are generally the smallest of the generally the smallest of the protozoa .protozoa .

It is a flagellate in the intestines of It is a flagellate in the intestines of termites which enable them to eat termites which enable them to eat wood. Both organisms wood. Both organisms benefit…..what kind of relationship benefit…..what kind of relationship do they have?do they have?

c) Flagellatesc) Flagellates

have one or several have one or several long, whip-like long, whip-like projections called projections called flagella poking out of flagella poking out of their cells. their cells.

they swim by waving they swim by waving their flagella, using their flagella, using them much like a fish them much like a fish uses its tail to push uses its tail to push itself through water. itself through water.

Chilomonas

Euglena

GiardiaGiardia

a) Ciliatesa) Ciliates have hair-like have hair-like

projections called projections called ciliacilia

They use the hairs to They use the hairs to help food particles help food particles get sucked in to get sucked in to themthem

beat their cilia in a beat their cilia in a rhythmic pattern to rhythmic pattern to move alongmove along

They are usually the They are usually the largest protists and largest protists and eat other protists.eat other protists.

paramaceium

The last of the Protozoans come from The last of the Protozoans come from the phylum, the phylum, SporozoaSporozoa..

These are parasitic and nonmotile.These are parasitic and nonmotile.

For example……For example……

Plant-like protists arePlant-like protists are algaealgae..

AlgaeAlgae are eukaryotic autotrophs. are eukaryotic autotrophs.

They, along with other eukaryotic They, along with other eukaryotic autotrophs, form the foundation of autotrophs, form the foundation of Earth’s food chains.Earth’s food chains.

They produce much of Earth’s They produce much of Earth’s oxygen.oxygen.

There are three There are three unicellularunicellular phyla of phyla of algae:algae:

Phylum Phylum EuglenophytaEuglenophyta

Phylum Phylum BacillariophytaBacillariophyta

Phylum Phylum DinoflagellataDinoflagellata

Members of first phylum of algae, Members of first phylum of algae, EuglenophytaEuglenophyta,, are both are both plant-likeplant-like and and animal-likeanimal-like..

Euglena are Euglena are autotrophsautotrophs since they since they make food from sunlight andmake food from sunlight and

HeterotrophsHeterotrophs since they ingest food since they ingest food from surrounding water.from surrounding water.

The second unicellular algae, The second unicellular algae, DiatomsDiatoms, are photosynthetic , are photosynthetic autotrophs.autotrophs.

They have shells of silica.They have shells of silica.

They make up a large portion of the They make up a large portion of the world’s phytoplankton which is world’s phytoplankton which is Earth’s largest provider of oxygen.Earth’s largest provider of oxygen.

DIATOMS

The third unicellular algae, The third unicellular algae, DinoflagellataDinoflagellata, are a major , are a major component of marine phytoplankton.component of marine phytoplankton.

These algae have at least two These algae have at least two flagella set at right angles to each flagella set at right angles to each other and thick cell walls made of other and thick cell walls made of cellulose plates.cellulose plates.

Blooms of dinoflagellates cause “Blooms of dinoflagellates cause “Red Red TideTide.”.”

MulticellularMulticellular algae are classified by algae are classified by color.color.

RhodophytaRhodophyta are red seaweeds. are red seaweeds.

They are found in warm or cold They are found in warm or cold marine environments along coast marine environments along coast lines in deeper water.lines in deeper water.

They absorb green, violet, and blue They absorb green, violet, and blue light waves. These light waves are light waves. These light waves are able to penetrate below 100 meters. able to penetrate below 100 meters.

Phylum PhaeophytaPhylum Phaeophyta is made up of the is made up of the brown algaebrown algae..

They are found in cool saltwater along rocky coasts.They are found in cool saltwater along rocky coasts.

Giant Kelp are the largest and most complex brown Giant Kelp are the largest and most complex brown algae. They have hold fasts and air bladders.algae. They have hold fasts and air bladders.

The last of the multicellular algae are the The last of the multicellular algae are the green algae from thegreen algae from the Phylum chlorophytaPhylum chlorophyta..

Most green algae are found in fresh water Most green algae are found in fresh water habitats.habitats.

A Volvox is a hollow boll composed of hundreds of flagellated cells in a single layer.

Chlamydomonas are actually unicellular and flagellated.

Fungus-like protists, Fungus-like protists, MyxomycotaMyxomycota and and OomycotaOomycota are decomposers. are decomposers.

Phylum Phylum MyxomycotaMyxomycota are made up of are made up of plasmodial slime molds.plasmodial slime molds.

Phylum Phylum OomycotaOomycota is made up of is made up of water molds and downy molds.water molds and downy molds.

Slime MoldsSlime Molds-weird-weird Slime molds have traits like both Slime molds have traits like both

fungi and animals. During good fungi and animals. During good times, they live as independent, times, they live as independent, amoeba-like cells, dining on fungi amoeba-like cells, dining on fungi and bacteria. and bacteria.

Slime Molds ContinuedSlime Molds Continued

But if conditions become uncomfortable—But if conditions become uncomfortable—not enough food available, the temperature not enough food available, the temperature isn't right, etc.—individual cells begin isn't right, etc.—individual cells begin gathering together to form a single gathering together to form a single structure. The new communal structure structure. The new communal structure produces a slimy covering and is called a produces a slimy covering and is called a slug because it so closely resembles the slug because it so closely resembles the animal you sometimes see gliding across animal you sometimes see gliding across sidewalks. The slug oozes toward light.sidewalks. The slug oozes toward light.

Slime Molds Continued.Slime Molds Continued.

When the communal cells sense that When the communal cells sense that they've come across more food or they've come across more food or better conditions, the slug stops and better conditions, the slug stops and become independent again.become independent again.

Water molds from the Phylum Water molds from the Phylum Oomycota are classified as protists Oomycota are classified as protists because they have flagellated because they have flagellated reproductive cells.reproductive cells.

Downy mildews parasitize plants and Downy mildews parasitize plants and are decomposers in freshwater are decomposers in freshwater ecosystems.ecosystems.

How are protists harmful?How are protists harmful?

MalariaMalaria is caused by a sporozoan is caused by a sporozoan (a parasitic (a parasitic

protist)protist) enters through the Anopheles mosquitoenters through the Anopheles mosquito

African Sleeping sicknessAfrican Sleeping sickness *Flagellates called trypanosomes*Flagellates called trypanosomes Cause fever and sleepinessCause fever and sleepiness http://www.utm.edu/departments/cece/old_site/seventh/7D2.shtmlhttp://www.utm.edu/departments/cece/old_site/seventh/7D2.shtml