Biology

Protist characteristicsProtists are organisms that do not fit into any

other kingdom. They can either by uni-celled or simple multicellular. They can be animal-like, plant-like, or fungus-like.

Protists are made up of eukaryotic cells, each containing a nucleus and other organelles.

Protist characteristicsA hypothesis for how eukaryotic cells arose:

From prokaryotes that obtained organelles via endosymbiosis.

Protists are often classified:By how the resemble fungi, plants, or

animalsMost protists are unicellular such as an

amoeba. Some of these unicellular protists form colonies in which several cells are joined into a larger body, such as Volvox.

Protist characteristicsA few protists are multicellular, such as

Brown algae. They have specialized regions for reproduction, photosynthesis, and attachment to the ocean floor, but lack true tissues and organs.

Protist characteristicsTwo ways in which protists obtain energy:

AutotrophyHeterotrophy

Protist characteristicsProtists move via

FlagellaCiliaPseudopodia

Protist characteristicsProtists reproduce:

Asexually either binary or multiple fission

Sexually conjugation

Animal-Like ProtistsPhylum Protozoa

Single-celled protists that can move independently without cilia or flagella

Have pseudopodia which are large, rounded cytoplasmic extensions that function both in movement and feeding. They engulf small organisms.

Move by amoeboid movement, which is a form of cytoplasmic streaming.

An example of a Protozo is an AmoebaHarmful to humans in that some can live in

human intestines and attack the lining, and may cause disease

Animal-Like ProtistsPhylum Ciliophora

They share one key feature: they have cilia which are: short, hair like cytoplasmic projections that line the cell membrane.

Cilia make it possible for these protists to move.

An example of Ciliophora is Paramecia.The process in which two Paramecia come

together after meiosis to exchange parts of their genetic material is called conjugation.

Plant-like ProtistsAlgae

Many plant-like protists are known as algae.Algae are autotrophic protists and have

chloroplasts and produce their own carbohydrates by photosynthesis, as plants do. They do not have true roots, stems, or leaves.

Plant and Animal-like ProtistsPhylum Euglenophyta

Phylum Euglenophyta contain flagellated unicellular algae called euglenoids, which are both plant-like and animal-like.

How are they like plants? Autotrophic, contain chlorophyll Have contractile vacuole and chloroplast

How are they like animals? Lack a cell wall and are highly motile If raised in dark, do not form chloroplast and

become heterotrophs

Plant and Animal-like ProtistsWhere do you find Euglena?

In fresh water, especially water polluted by excess nutrients

How do they move?Long flagellum

Fungus-like ProtistsSlime mold- can either be:

*mobile, amoeba-like feeding *sessile, reproductive spore-

bearing form

Water mold- composed of branching filaments of cells

Protists and HumansEnvironmental roles of protist producers:

Produce oxygenForm the foundation of food websRecycle materials

Protists and HumansProtists symbiosis:

Corral, fungi, and termites

Protists and HumansProtists for food:

Seaweeds are eaten directlyByproducts are used to make cheeses, ice

cream, salad dressing, and bakery items.

Protists and HumansPeople use:

Alginate is used in cosmeticsCarageenan is used in gelatin capsulesAgar is used to culture microbes

Protists and HumansWhat is Giardiasis?

Caused by Giardia lambliaReults in diarrhea and cramps

Protists and HumansWhat is Cryptosporidiosis?

Caused by Cryptosporidium paruumCharacterized by diarrhea

Protists and HumansWhat is Trichomoniasis?

Caused by Trichomona vaginalisAn STD that causes discolored discharge

and genital itching.