KINGDOM PROTISTA

Chapter 21

Kingdom Characteristics

• Eukaryotic

• Mostly unicellular—many multicellular

• Autotrophic, Heterotrophic, and both

• Cell wall may or may not be present

Evolutionary Importance

• Protists are considered to be the

ancestors of the three multicellular

kingdoms—fungi, plant, animal

Major Divisions of Protists

Plant-like Protists (Algae)

Animal-like Protists (Protozoans)

Fungus-like Protists (Slime Molds)

Plant-like Protists—Algae

• Autotrophic

• Contain cell walls

• Some are mobile—many are

immobile

Volvox

Kelp

Green, Red, and Brown

Algae• Cellular Organization:

– Multicellular (Red and Brown)

• Green algae can be either

• Nutrition: – Photosynthetic (Autotrophic)

• Locomotion: Non-motile

• Habitat: – Red Algae: Marine Green Algae: Fresh, Marine, Soil

Brown Algae: Marine

• Classified by their pigment

• Green, Red, or Brown (kelp) Algae – Used in many foods such as pudding, jelly, jelly beans,

ice cream, marshmallows, salad dressing

Dinoflagellates

• Cellular Organization: – Unicellular

• Nutrition: – Autotrophic

• Locomotion: 2 Flagella

• Habitat: – Fresh and Marine

• Cause Red Tides

Diatoms

• Cellular Organization: – Unicellular

• Nutrition: – Autotrophic

• Locomotion: Non-motile

• Habitat: – Fresh and Marine

• Shells made out of silica (glass-like)

Euglenoids

• Cellular Organization: – Unicellular

• Nutrition: – Heterotrophic/Autotrophic

• Locomotion: 1 or 2 Flagella

• Habitat: – Aquatic

• Ex: Euglena

Animal-like Protists--Protozoans

• Heterotrophic

• All are unicellular

• None contain cell walls

• Most can move– Cilia- hair-like projections

– Flagella- whip-like tail

– Pseudopod- “false foot”

• Immobile ones are parasites

Amoeba

• No cell wall gives them flexibility

• Cellular Organization:

– Unicellular

• Nutrition:

– Heterotrophic

• Locomotion: Pseudopods

• Habitat:

– Fresh and salt water

• Some may cause disease (they are

parasites)

Foraminiferans (“Forams”)

• Cellular Organization: – Unicellular

• Nutrition: – Heterotrophic

• Locomotion: Pseudopods

• Habitat: – Salt water

• Calcium Carbonate Shells

Kinetoplastids (Flagellate)

• Cellular Organization: – Unicellular

• Nutrition: – Heterotrophic

• Locomotion: flagella

• Habitat: free living and parasitic

• Ex: Trypanosomes causes African Sleeping Sickness

Ciliates

• Cellular Organization:

– Unicellular

• Nutrition:

– Heterotrophic

• Locomotion: cilia

• Habitat: fresh water and marine

• Ex: Paramecium, Vorticella and stentor

Sporozoans

• Cellular Organization: – Unicellular

• Nutrition: – Heterotrophic

• Locomotion: Non-motile

• Habitat: parasitic

• Ex: – Plasmodium-Malaria

Fungus-like Protists—Slime Molds

• Heterotrophic decomposers

• Contain cell walls

• Multicellular

• Exist in different forms and produce spores

• Reproduce by forming spores

• 3 types: water molds, downy mildews, and slime molds

Slime Molds

• Cellular Organization:

– Multicellular

• Nutrition:

– Heterotrophic

• Locomotion: amoeboid movement

• Habitat: cool, moist, shady places

Water/Downy Molds

• Cellular Organization: – Multicellular

• Nutrition: – Heterotrophic (either parasites or feed

on dead organic matter)

• Locomotion: amoeboid movement

• Habitat: cool, moist, shady places

• Cause of the Irish potato famine in 1845-1850 that killed 1 million people

Ecological Importance of Protists

• Autotrophic protists are primary component of PHYTOPLANKTON

• These organisms carry out 70 – 80% of the world’s photosynthesis

• Phytoplankton and ZOOPLANKTON (heterotrophic protists) are the base of most of the world’s food chains

Negative Contributions of Protists

• Many cause disease

– Malaria, sleeping sickness, amebic

dysentery, etc.

• Responsible for “Red Tide” that poisons shell fish

• Algae blooms result in fish kills

Concept Map

• Create a Concept Map of Kingdom Protista that includes the following information:

– Type of protist (animal, plant, or fungus-

like)

– Cellular Organization

– Mode of Nutrition

– Mode of Movement

– Examples of each type of protist