Protists are unicellular eukaryotic organisms that can be categorized into three main groups: animal-like protists, plant-like protists, and fungus-like protists. They were some of the first organisms on Earth and include microbes that can cause disease in humans. While similar to bacteria in being microscopic and unicellular, protists differ in having a nucleus and generally living as individual eukaryotic cells. Plant-like protists, or algae, can be autotrophs capable of photosynthesis, and fungus-like protists reproduce using spores.

1. Kingdom: Protista
Protists are unicellular organisms that have a nucleus.

2. Similar to Bacteria
 Unicellular
 One of the first groups of living things on Earth.
(1.5 billion years ago.)
 Microscopic
 Can cause disease.
 Can be parasites

3. Difference from Bacteria
 Has a nucleus.
 Live in watery environment.
 Generally live as individual cells.
 Protists vary greatly in appearance and function.

4. 3 Categories
 I. Animal-like Protists.
 II. Plant-like Protists.
 III. Fungus-like Protists.

5. I. Animal-like Protists
 Protozoan means “First Animal”.
 Cells contain a nucleus.
 Cells lack a cell wall.
 They are heterotrophs.
 Most can move on their own.

6. 4 Groups of Animal-like
Protists
 1. Sarcodines (SAHR-koh-dighnz)
 2. Ciliates (SIHL-ee-ihts)
 3. Flagellates (FLAJ- ehl-ihts)
 4. Sporozoans (spohr-oh-ZOH-uhnz)

7. 1. Sarcodines
 Have pseudopods (Greek:“false foot”)
 Extensions of the cell membrane and cytoplasm.
 Pseudopods are used for movement and to
capture food.
 Many have shells.
 These shells form limestone, marble and chalk.

8. One type:
 Most familiar
Sarcodine.
 Pseudopods:
 Blob shaped.
 Contractile
Vacuoles: controls
amount of water inside
 Food Vacuole: where
food is digested.

9. Split Personality
 Amebas reproduce
by dividing into two
new cells (binary
fission).
 Amebas can
respond to their
environment.
 They are sensitive to
light and some
chemicals.

10. 2. Ciliates
 Have cilia on the
outside of their cells.
 Tiny hair-like
projections used for
movement, to gather
food and as feelers.

11. Type: Paramecium
 Pellicle: tough outer
wall.
 Slipper shaped
 Oral groove: like the
mouth
 Gullet: holds food.
 Food Vacuole: digests
food.
 Anal Pore: removes
wastes
 2 Contractile Vacuoles
 2 Nuclei
 Reproduces by either
binary fission or
conjugation.

12. 3. Flagellates
(Zooflagellates)
 Have a Flagellum: a
long whip-like
structure used for
movement.
 Many live in animals
 Symbiosis a close
relationship, at least
one benefits.
 Mutualism: when
both partners benefit.

13. 4. Sporozoans
 All Sporozans are parasites.
 They feed on cells and body fluids.
 Form from Spores (tiny reproductive cells).
 Pass from one host to another.
 Pass from ticks, mosquitoes or other animals to
humans.

14. II. Plant-like Protists
(Algae)
 Unicellular and Multicellular
 Colonies (groups of unicellular protists)
 Can move on their own
 Autotrophs: make their own food from simple materials using
light energy (photosynthesis).
 70% of the Earth’s oxygen is produced by Plant-like Protists!
 Pigments: chemicals that produce color

15. 6 Groups of Plant like
Protists
 Euglenoids (yoo-GLEE-noydz)
 Diatoms (DIGH-ah-tahmz)
 Dinoflagellates (digh-noh-FLAJ-eh-layts)
 Red Algae
 Green Algae
 Brown Algae

16. 1. Euglenoids
 Green
 Unicellular
 Live in fresh water
 Autotrophs, but can be
heterotrophs under certain
conditions.
 Flagella
 Eyespot: sensitive to light.
 Chloroplasts
 Pellicle

17. 2. Diatoms
 Unicellular
 10,000 living species.
 Aquatic
 Glass like cell wall
 Diatomaceous earth:
course powder that
comes from dead
diatoms (toothpaste,
car polish & reflective
paint.

18. 3. Dinoflagellates
 Unicellular
 Cell walls are like
plates of armor.
 Two flagella
 Spins when it moves.
 Colorful (pigments)
 Can glow in the dark.
 Causes Red Tide

19. Red Algae
 Multicellular seaweeds
 Live in deep ocean waters
 Used for ice cream and hair
conditioner
 Used as food in Asia

20. Green Algae
 Most are unicellular
 Some form colonies
 Few are multicellular
 Can live in fresh and salt
water and on land in damp
places.
 Very closely related to green
plants.

21. Brown Algae
 Commonly called seaweed
 Can contain brown, green,
yellow, orange and black
pigments.
 Attach to rocks
 Have air bladders
 Giant Kelp can be 100
meters long!
 Used as food thickeners

22. III. Fungus-like Protists
 Heterotrophs
 Have cell walls.
 Many have flagella and are able to move at some point in their
lives.
 Three types: Slime Molds, Water & Downy Molds
 Reproduce with Spores (tiny cell that is able to grow into a new
organism)

23. Water & Downy Molds
 Live in water or moist places.
 Tiny threads that look like fuzz.
 Attack food crops
 Caused the Irish Potato
Famine.

24. Type:
 Reproduce by Fruiting
Bodies:
 The Fruiting Bodies
contain Spores.
 At first they look like
ameba, then later they
look like mold.
 Live on moist shady
places.
 Feed on bacteria and
other microorganisms.