Protists

The Protists• Protists are unicellular eukaryotic cells. (Unlike

bacteria which are unicellular prokaryotic cells.)• Do you remember the differences between

prokaryotes and eukaryotes???• Protists are like the junk drawer of microbiology –

there is a huge amount of diversity within this kingdom – but – they are all single-celled eukaryotes.

• Protists can be generally classed into one of three groups:– Animal-like– Fungus-like– Plant-like

Animal-like Protists• Animal-like protists are those that

must ingest (eat) things from the environment around them.

• There are four groups of animal-like protists:– Zooflagellates– Amoebas– Ciliates– Sporozoans

Zooflagellates• The zooflagellates

are animal –like protists that are easily recognized by their flagella – a long whip-like structure used to propel it through the water.

• Zoo = animal• Many zoo-flagellates

can cause sickness if ingested in contaminated water.

• Trypanosoma gambiensis

• Giardia lamblia

Amoebas• Amoebas are

known for their ever-changing body shape.

• They use pseudopods to move and reach out to grab food.

• The food is engulfed using phagocytosis.

Ciliates• The ciliates are

covered in cilia. The back ground to this slideshow is a ciliated protist.

• They have a rigid outer layer called the pellicle that maintains a stable shape (unlike the amoebas).

• Paramecium

Sporozoans• Sporozoans are called

such because they use spores as part of their reproductive cycle.

• They are non-motile and parasitic. They need to be passed on from host to host and they live using the host’s resources.

• Plasmodium vivax

Malaria…The Ugly Truth!

Fungus-like Protists• These protists are heterotrophic

and most are decomposers that feed on dead and decaying plants and animals. (Hence the title “fungus-like”.)

• In this subsection of protists, you will find the acellular slime moulds, cellular slime moulds and the water moulds!

• Lets move on…

Plant-like Protists• Plant-like protists contain chlorophyll

and carry out photosynthesis. They are autotrophs.

• You will find the euglenoids, and algae in this group.

• These two groups differ from each other in a few ways:– Euglenoids have the ability to be heterotrophic

or photosynthetic while most algae are only photosynthetic.

– Euglenoids have flagella, some algae do but not all.

– Euglenoids a free living while some algae live in large colonies.

Euglena vs. Algae!!!• Euglena!• Diatoms!• Dinoflagellates!• Red Tide!• Algae!• Algal Bloom!• Stupid guy

drinking algae!

That’s All I Got…