Kingdom ProtistaKingdom Protista

General IntroductionGeneral Introduction Protists first appeared in the fossil Protists first appeared in the fossil

records about 1.5 billion years agorecords about 1.5 billion years ago

Demonstrate an important Demonstrate an important evolutionary advancement, a evolutionary advancement, a membrane bound nucleusmembrane bound nucleus

Protist Introduction Protist Introduction ContinuedContinued

Contain organelles such as Contain organelles such as ribosomes, mitochondria, and ribosomes, mitochondria, and lysosomeslysosomes

These structures provide a more These structures provide a more efficient method of using available efficient method of using available nutrientsnutrients

Members of the Kingdom Protista are Members of the Kingdom Protista are the simplest of the the simplest of the eukaryoteseukaryotes

Reproduce sexually and asexuallyReproduce sexually and asexually

Require an aquatic environmentRequire an aquatic environment

Some move around and act like Some move around and act like animals, others perform animals, others perform photosynthesis like plants, and still photosynthesis like plants, and still others seem to "think" they're fungi!others seem to "think" they're fungi!

Where Do Protists Fit?Where Do Protists Fit?

Why Are Protists Important?Why Are Protists Important?

Autotrophic protists, like Autotrophic protists, like phytoplankton, produce a significant phytoplankton, produce a significant portion of the Earth’s oxygenportion of the Earth’s oxygen

Play an important role in the carbon Play an important role in the carbon cyclecycle

Important producers and consumers Important producers and consumers in food chains.in food chains.

Act as a road map for evolution!Act as a road map for evolution!

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..

Kindom Kindom ProtistaProtista

The Kindom Protista has traditionally The Kindom Protista has traditionally been referred to as the “been referred to as the “junk drawerjunk drawer” ” kingdom because any eukaryote that is kingdom because any eukaryote that is not classified as a green plant, fungus, not classified as a green plant, fungus, or animal tends to get placed there.or animal tends to get placed there.

Protists are microscopic and unicellularProtists are microscopic and unicellular

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

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

3 types of protists:3 types of protists:

1) Plant-like protists (algae) are 1) Plant-like protists (algae) are autotrophsautotrophs – – they they contain chloroplasts and make their own contain chloroplasts and make their own food.food.

2) Animal-like protists (protozoans) are2) Animal-like protists (protozoans) are heterotrophsheterotrophs – they are not capable of – they are not capable of making their own foodmaking their own food

3) Fungus-like protists (slime molds) are3) Fungus-like protists (slime molds) are also also heterotrophsheterotrophs – they are not capable of – they are not capable of making making their own foodtheir own food

ProtozoansProtozoans are animal-like protistsare animal-like protists (all are (all are heterotrophsheterotrophs))

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 animalsmany species behave like tiny animals—specifically, they hunt and gather —specifically, they hunt and gather other microbes as food.other microbes as food.

4 groups of protozoans: classified 4 groups of protozoans: classified according to how they move.according to how they move.

Protozoans consist of Protozoans consist of 4 groups 4 groups which are which are classified according to their type of classified according to their type of locomotion.locomotion.

Protozoans digest their food in stomach-like Protozoans digest their food in stomach-like compartments called vacuoles compartments called vacuoles

<<vac-you-ohlsvac-you-ohls>>..

Protozoans range in size from 5 to 500 µm Protozoans range in size from 5 to 500 µm (.005 -.500 mm) in diameter. They can be (.005 -.500 mm) in diameter. They can be classified into three general groups based on classified into three general groups based on how they move.how they move.

Group 1 is the Phylum Group 1 is the Phylum SarcodinaSarcodina. These are . These are the the amoebaeamoebae < <ah-me-beeah-me-bee>>

Linnaeus named the organism “chaos, Linnaeus named the organism “chaos, chaos” when he saw it for the first timechaos” when he saw it for the first time

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.

Amoeba ProteusAmoeba Proteus

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.

Group 2 is theGroup 2 is the Phylum Phylum MastigophoraMastigophora, , also referred to as the also referred to as the flagellatesflagellates..

Are generally the smallest of the Are generally the smallest of the protozoa and have one or more protozoa and have one or more flagellaflagella

Flagellates use their flagella to move.Flagellates use their flagella to move.

Some parasitic flagellates (Some parasitic flagellates (GiardiaGiardia, , CryptosporidiaCryptosporidia) can form cysts to ) can form cysts to spread from host-to-host through spread from host-to-host through contaminated watercontaminated water

GiardiaGiardia

CryptosporidiumCryptosporidium

Group 3 is theGroup 3 is the Phylum Phylum Ciliophora. Ciliophora. These These are also called the ciliates. are also called the ciliates. These are generally the largest These are generally the largest protozoa. protozoa.

They are covered with hair-like They are covered with hair-like projections called projections called ciliacilia and they eat and they eat the other two types of protozoa as the other two types of protozoa as well as bacteriawell as bacteria..

Ciliates are found in every aquatic Ciliates are found in every aquatic habitat.habitat.(example: (example: ParameciumParamecium))

Paramecium feedingParamecium feeding

Group 4 is the Phylum Group 4 is the Phylum SporozoaSporozoa; the last ; the last group of protozoansgroup of protozoans

These are exclusively parasitic and non-These are exclusively parasitic and non-motile (lack a means of independent motile (lack a means of independent locomotion)locomotion)

Dependent on host(s) for nutrition and Dependent on host(s) for nutrition and movement.movement.

Are characterized by a spore-like stage in Are characterized by a spore-like stage in their life cycle (their life cycle (Plasmodium vivax Plasmodium vivax – text. p. – text. p. 231; causes 231; causes malariamalaria))

Plant-like protists Plant-like protists are traditionally are traditionally referred to asreferred to as 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 Euglenophyta (Euglena)Euglenophyta (Euglena) Phylum Phylum Chrysophyta (Diatoms)Chrysophyta (Diatoms) Phylum Phylum Pyrrophyta Pyrrophyta

(Dinoflagellates)(Dinoflagellates)

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. Are also…make food from sunlight. Are also…

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

The second unicellular algae, The second unicellular algae, ChrysophytaChrysophyta, 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, Phylum Phylum Pyrrophyta Pyrrophyta , are a major component of , are a major component of marine phytoplankton.marine phytoplankton.

Also called the “Dinoflagellates”Also called the “Dinoflagellates”

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

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

Fungus-like protists:Fungus-like protists:

Phylum Gymnomycota Phylum Gymnomycota are are heterotrophic decomposersheterotrophic decomposers

slime molds; organisms having a slime molds; organisms having a noncellular and multinucleate noncellular and multinucleate creeping vegetative phase and a creeping vegetative phase and a propagative spore-producing stagepropagative spore-producing stage

comprised of:comprised of: MyxomycetesMyxomycetes and and AcrasiomycetesAcrasiomycetes

Slime MoldsSlime Molds

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

if conditions become uncomfortable—not if conditions become uncomfortable—not enough food available, the temperature isn't enough food available, the temperature isn't right, etc.—individual cells gather together right, etc.—individual cells gather together to form a single structure called a slug to form a single structure called a slug because it so closely resembles the animal because it so closely resembles the animal you sometimes see gliding across sidewalks. you sometimes see gliding across sidewalks.

The slug oozes towards light.The slug oozes towards light.

Slime mold formsSlime mold forms