Protist KingdomChapter 19

What makes a protist a protist?

• Protists are the most diverse kingdom• They were the very first eukaryotes

– Gave rise to fungi, plant, and animal kingdom

• A protist is any eukaryote that is not a fungus, plant or animal!

• Protists may be unicellular or multicellular

• Can reproduce sexually or asexually• Protists are divided into 14 different

phyla:

Rhizopoda (amoebas)

• Move by flexible extensions called pseudopodia

• no cell walls or flagella• Engulf food by phagocytosis• Live in fresh water, salt water,

and in the soil• Can cause disease

– dysentery

Rhizopoda (amoebas)

FeedingAmoeba

Foraminifera (forams)

• Live in marine environments• Have porous shells called tests• Resemble a tiny snail• Uses long thin projections of

cytoplasms extended through holes in the test to swim and capture prey

• Calcium carbonate shells of dead forams help form limestone

Foraminifera (forams)

Bacillariophyta (diatoms)

• Photosynthetic• Unicellular• Have double shells (diatoms)• Abundant in oceans and lakes• Usually reproduce asexually• Empty shells make diatomaceous

earth– Used in abrasives, car paint, animal

feeds, whitening toothpaste and as an insect repellant

Bacillariophyta (diatoms)

Bacillariophyta (diatoms)

Bacillariophyta (diatoms)

Chlorophyta (green algae)

• Autotrophic (photosynthetic)– Contains chlorophyll

• Most are unicellular but some are multicellular

• Live in saltwater, freshwater, and damp soil

Chlorophyta (green algae)

Chlorophyta (green algae)

Rhodophyta (red algae)

• Multicellular• Photosynthetic

– Red pigment absorbs light at greater depths

Phaeophyta (brown algae)

• Multicellular• Include kelp, one of the largest

organisms on Earth

Algae Uses

• Algae are used in many things:– used as a thickener and to stabilize

ingredients in dairy products, paint and cosmetics (carrageenan)

– used in food and food additives and also in bacterial culture (agar)•Nori, Japanese seaweed paper is used

in sushi, soup and many other dishes – it is a mixture of different species of red algae

Dinoflagellata

• Most are marine, few freshwater• Protective cellulose coat• Some produce powerful toxins

– Cause “red tides”

Zoomastigina

• Unicellular• One or many flagellum• One species Trichonympha is

symbionic with termites and digest wood

Euglenophyta

• Live in freshwater

• Have two flagella• Some

photosynthetic• Have eyespots to

sense light• Euglena in Motio

n

Ciliophora

• Complex protists• Use cilia to swim• Have two nuclei:

macronuclei and micronuclei

• Reproduction usually mitosis

• Feeding Paramecia

Slime MoldsMyxomycota and Oomycota• Cellular slime

molds are unicellular but in times of stress the come together to form a “slug”

Slime MoldsMyxomycota and Oomycota

• Plasmodial slime molds are a group of organisms that stream along together as a plasmodium

Apicomplexa (sporozoans)

• Parasitic• Often transmitted from host to

host through blood-feeding insects

• Example: malaria– Malaria kills more people globally

than any other infectious disease