Protists

PROTISTS

• We have already learned about Bacteria and Viruses

• Now it’s time to study ProtistsMICROBES:1. Viruses2. Bacteria3. Protists4. ?

PROTISTS

• Protists can be very different from each other.• All protists are EUKARYOTES = DNA is found in

a nucleus• Some are like animals, some are like plants,

some are like fungi, but they are a little different. So they are Protists.

• All live in moist environments• Some are UNICELLULAR, while others are

MULTICELLULAR

PROTISTS

• Some are HETEROTROPHS

• Some are AUTOTROPHS

• Some are BOTH

What are heterotrophs? Autotrophs?

Imagine being both….

PROTISTS

3 CATEGORIES OF PROTISTS:

1. Animal-like Protists

2. Plant-like Protists

3. Fungus-like Protists

Animal-like PROTISTS

ALSO CALLED PROTOZOANS• All animal-like protists are HETEROTROPHS• Most are able to move from place to place to

get their food.4 GROUPS OF PROTOZOANS:1. Protozoans with PSEUDOPODS2. Protozoans with CILIA3. Protozoans with FLAGELLA4. Protozoans that are PARASITES

Protozoans With Pseudopods

• Sarcodines have PSEUDOPODS = means “false foot”. Part of the cytoplasm bulges towards one location, and the rest of the organism follows.

• Sarcodines include: Amoebas

• Amoebas also have CONTRACTILE VACUOLES = a structure that collects extra water then squirts it out from the cell.

An Amoeba

Protozoans With Cilia

• Ciliates have CILIA = hair-like projections from cells that move with a wavelike motion.

• Ciliates include: Paramecium

• Paramecium have 2 Nuclei, 2 contractile vacuoles, and can reproduce asexually and sexually.

Paramecium

Protozoans with Flagella

• Flagellates have flagella

• Some of these live inside other organisms.

• SYMBIOSIS = a close relationship in which at least one of the species is helped.

• MUTUALISM = a close relationship in which both species are helped.

Protozoans that are Parasites

• Some protozoans feed on the cells of their host and cause harm.

Plant-like PROTISTS

• Commonly called ALGAE (that green stuff on a pond)

• All are AUTOTROPHSTHE DIFFERENT GROUPS OF ALGAE:

1. Diatoms2. Dinoflagellates3. Euglenoids

4. Red Algae5. Green Algae6. Brown Algae

Euglenoid

Fungus-like Protists

• All are HETEROTROPHS• All have Cell Walls• All use SPORES to reproduce• All can move at some point in their lives

THE 3 KINDS OF FUNGUS-LIKE PROTISTS:

1. Slime molds

2. Water molds

3. Downy molds

Slime Mold

Living or

Non-Living

Living

Structure • Depends on type• They can look like animal or plant cells

Different Types

of Protists

• Protozoans (Animal-like Protists)• Algae (Plant-like Protists)• Fungus-like Protists

How they

Reproduce

Sexually & Asexually

Size of Protists • Vary from unicellular to multi-cellular• Some are microscopic while others you can see with your eyes alone.

Good things Protists do

• Symbiosis and mutualism with other organisms.

• Algae are main source of oxygen in atmosphere.

• Provide food for other organisms

• Household products (diatoms)

Bad things Protists do

• Cause disease

• Attack crops