PROTISTS

Protist classification• eukaryotic

• mostly unicellular

• The protist kingdom is a “dumping ground” –includes organisms that have exceptions to the many rules that scientists attempt to apply to them.

Kingdom Protista

Animal like -- Protozoa (zooplankton)Plant like-- Alga (phytoplankton)Fungi like -- Slime and Water Molds

Protozoa

• Heterotrophic (eat dead things or other organisms)

• No cell walls• Are all capable of asexual

reproduction usually by binary fission

What distinguishes these? By

locomotion

Animal-like Protists-ProtozoaPhylum Sarcodinian -move with pseudopods

-ex. amoebas (& foraminifera and radiolaria) -One type of amoeba causes dysentery.

Phylum Ciliphora - ciliates (cilia)-ex Paramecium, Blepharisma, Stentor & Vorticella.

Phylum Zooflagellates - flagellates also called zoomastigina. Many cause disease in humans. -ex Trypanosoma which causes African s.s.; or Giardia

Phylum Sporozoa -nonmotile, spore bearing, -all parasitic-ex. Plasmodium which causes malaria.

Sarcodinian • Locomotion:– pseudopodia all– allows for great flexibility

• Types (life styles)– Amoeba

marine/terres/parasitic

• Distinctive feature– Ameobiod movement– Cytoplasmic streaming

Sarcodinian

• Examples– Amoeba proteus– Entamoeba hixtolyca (causes amoebic dysentery)

Nucleus

Water Vacuole

Food vacuole

Pseudopodia

Contractile Vacuole

(not shown)

Ciliaphorans• Locomotion

– cilia

• Lifestyle– most free living– aquatic

• Distinctive feature– two nuclei

• macro: boss• micro: sex. repro

• Examples– Paramecium– Stentor, Vorticella– Blepherisma

Cilliates

Oral groove

Paramecium Conjugaton

Zooflagellates

(zoomastigote)

• Locomotion– flagella

• Lifestyle– most free-living– some parasitic

• Distinctive features– most carried by

vectors– from reservoir

• Examples – Trypanosoma African

s.s.– Giardia

Vector

• An organism– usually an arthropod or mollusca

• Carries a pathogen– without being effected by it

• Example : Bubonic plague– Flea carries the disease

Flagellates

Sporozoans

(Apicomplexians

)

• Locomotion– none (flagella in some

phases)

• Lifestyle– all parasitic

• Examples– Plasmodium vivax

• causes Malaria

– Toxoplasma gondii• causes toxoplasmosis

Sporozoans

Mosquito Facts

• Mosquitoes are responsible for more human death than any other living creature.

• Male mosquitoes do not bite. The real risk is from female mosquitoes which bite when in search of a blood meal to provide protein for their eggs.

• Most adult mosquitoes live for about two weeks.

• There are over 2,500 species of mosquitoes in the world.

• The welts that appear after a mosquito leaves isn't from the bite - it's an allergic reaction to saliva the mosquito injected under the skin to prevent the blood from clotting

• Mosquitoes like dark areas and will suck the juice out of plants in order to live - including tree leaves, grass, shrubs, etc

AlgaePlant like Protists

• Autotrophic (all have chlorophyll a)• Have cell wall• Alga are divided by pigments, cell wall

types, and food storage compounds

FYI• Thallus - body portion of an algae• Blue green algae are not protists at all-- they are Cyanobacteria, a

moneran (lab)• Watch the green algae, because of their similarities with them, they are

probably the ancestors of modern plants

Algae: Plant-like ProtistsUnicellular

• Phylum Euglenophyta– Euglena

• Phylum Chyrsophyta (Bacillariophyta) – golden algae – diatoms

• Phylum Pyrrophyta – fire algae – Dinoflagellates

Multicellular• Phylum Rhodophyta

– red algae– red seaweed.

• Phylum Phaeophyta – brown algae – kelp

• Phylum Chlorophyta – green algae– Volvox

Chlorophyta“green algae”

• Pigments (like plants)

– chl a,b – carotenoids

• Cell wall = cellulose (like

plants)

• Storage = starch (like plants)

• Ancestors of plants• Can be unicellular, filimentous, colonial, and multicellular• Motile - uni and colonial• Habitat – fresh water

Algae Structure• Unicellular

– single cell– phytoplankton

• Filamentous– the cells divide but do not separate

causing long strands– cells do not differentiate

• Colonial– groups of cells acting in a

coordinated manner

• Multicellular– Some differentiation

Example 1 of Chlorophyta“green algae”

Chlamydomonos- Unicellular

- Motile, Flagellated

Example #2 of Chlorophyta

“green algae”

• Spirogyra• Filimentous

- the cells divide but do not separate causing long strands-cells do not differentiate

Example #3 of Chlorophyta

“green algae”

• Volvox , Pandorina

• Colonial:Cells have different roles– flagellated

cells– photosynthetic– gametocytes

Cells not trully differentiated

Example #4 of Chlorophyta

“green algae”

• Ulva (sea lettuce)

• Multicellular• Reproduces by

alternation of generations

Pigments– chl a,c– carotenoids– Fucoxanthin

Phaeophyta“brown algae”

• Examples – kelp

parts of kelp

• holdfast, stipe, • blade, • bladder

– temperate seaweed

• All multicellular

• habitat– salt water

• nonmotile*

Phaeophyta“brown algae”

blade

bladder

stipe

holdfast

Rhodophyta“red algae”

• pigments– chl a– carotenoid

s– Phycoblins

• cell wall– CaCO3

Rhodophyta“red algae”

• examples– tropical – red seaweed

• multicellular• habitat

– salt water• nonmotile

“agar”

• pigments– chl a,c– carotenoids– peridinum

• cell wall– cellulose

• food storage– starch

Pyrrophyta“fire algae”

dinoflagellata

• Examples: dinoflagellates

• unicellular• habitat

– fresh/salt• motile:

– biflagellates

Pyrrophyta“fire algae”

PyrrophytaDinoflagellate

sred tidecause “red tide”

often phosphorescent

Algal bloom

Toxins

Chrysophyta“golden algae”

• Pigment– chl a,b – carotenoids– fucoxanthin

• cell wall– silica cell wall

• food storage– oil

Chrysophyta “golden algae”• Example: diatoms

• Unicellular (some colonial)

• motile : raphe• habitat

– salt/fresh water

• reproduction– asexual– sexual

FORM:

Diatomaceous Earth

Petroleum Deposits

Euglenophyta

• Pigment – chl a– chl b – carotenoids

• Cell Wall– protein pellicle

• Food Storage– polysaccharide

Euglenophyta•Examples:

– Euglena,– Astasia (can lose its

chloroplasts and become heterotrophic)

•all unicellular

• motile: flagella• Habitat

– fresh water

eyespot

Fungus-like protists• Heterotrophic with external

digestion.– Absorptive nutrition

• similar lifestyle as fungi• multicellular multinucleate

2 groups (based on cell type) • Water molds are composed of

filaments of cells. – Phylum Oomycota

• Slime molds are amoeba-like.– Phylum Myxomycota – Phylum Acrasiomycota

Oomycetes

• Known as– “water molds”

• have cellulose in cell wall

• ex water molds and downy mildews

• have branching filaments called hyphae

• Causes– one cause of

“ick”grows on decaying aquatic life

Oomycetes

Oomycetes

• Cell wall– cellulose

• Body structure– branching filaments– few cell walls

Oomycetes

• Causes– potato blight– root, fruit, crown rot– puckeye rot

Oomycetes

• Causes– downy mildew– round worm

parasite

Chytridiomycota

• Known as– Water Mold

• Reproduction– flagellated

sex cells

• Probable ancestor of modern fungi

Sprogyra with chytrid parasite

Chytridiomycota

• Habitat – aquatic

• Cell wall– chitin like fungi

• Body structure– long filaments

• Mostly Unicellular • Mostly Parasites

Myxomycota

• Example is plasmodial slime molds– multinucleate

Myxomycota

• Body structure– One enormous cell

(plasmodium)– many nuclei

•covered in slime sheath

•leaves a slime track

•Habitat : Terrestrial

Myxomycota

• Life Cycle (reproduction)– spends most of life as a plasmodium– produces fruiting bodies with gametes– gametes behave like amoebas– two gametes meet--> produce new

plasmodium

Myxomycota

• Life Cycle (reproduction)– spends most of life as a

plasmodium– produces fruiting bodies

with gametes– gametes behave like

amoebas– two gametes meet-->

produce new plasmodium

Acrasiomycota• Example is cellular

slime molds

Acrasiomycota

• Life Cycle– most of life as AMOEBA

• one nucleus• haploid

– in stress, come together • form “slug” or “grex”• send up fruiting body

– newly hatched cells are amoeba

b y locom otion

P seu d op od iaam oeb a

F lag e llag ia rd ia

N o m otionp lasm od iu m

C iliap aram ec iu m

A n im a l like

b y p ig m en tan d ce ll w a ll

U n ice llu la rflag e lla tes

G o ld en A lg aed ia tom s

F ire A lg aed in o flag e lla tes

B row n A lg aeke lp

R ed A lg aeseaw eed

G reen A lg ae

P lan t like

b y lifes tylean d ce ll typ e

W ater M o ldw /ce llu lose

W ater M o ldw /ch it in

Tru eS lim e M o ld

C e llu la rS lim e M o ld

F u n g i like

U n ice llu la rE u karyo tes