Type 1Type 2 Type 3a Type 3b Picture Representations of The Three Types of Protists

Kingdom Protista 9-simply-science-protista-video.htm

Characteristics of Protists 60,000 + species 60,000 + species Eukaryotes Eukaryotes Generally unicellular Generally unicellular 10 μm – 60 m 10 μm – 60 m Some have cell walls Some have cell walls Some are motile Some are motile Some have pigments Some have pigments Various methods of feeding Various methods of feeding Most are aerobic Most are aerobic Lack specialized features of fungi, plants and animals Lack specialized features of fungi, plants and animals Do not develop complex sex organs Do not develop complex sex organs Do not form embryos Do not form embryos

Classifying Protista They are divided into three major groups based on their type of nutrition: They are divided into three major groups based on their type of nutrition: 1. Protozoa (animal-like) heterotrophs that ingest or absorb their food heterotrophs that ingest or absorb their food 2. Algae (plant-like) autotrophs that carry out photosynthesis autotrophs that carry out photosynthesis 3. Slime Moulds and Water Moulds (fungi-like) heterotrophs heterotrophs

1. Protozoa 1. Protozoa 2. Algae 2. Algae 3. Slime Moulds and Water Moulds 3. Slime Moulds and Water Moulds

1. Protozoa They feed on other organisms, they may be dead organisms. Some are scavengers, predators, or parasitic. They feed on other organisms, they may be dead organisms. Some are scavengers, predators, or parasitic. They vary in shape and size. Most live as a single cell but some do form colonies. They vary in shape and size. Most live as a single cell but some do form colonies. They are generally classified in 4 phyla based on their locomotion They are generally classified in 4 phyla based on their locomotion

1a) Flagellates Phylum Zoomastigina Phylum Zoomastigina They have one or more flagellum They have one or more flagellum They have a hard, protective covering over their outer membrane They have a hard, protective covering over their outer membrane

1b) Sarcodines Phylum Sarcodina Phylum Sarcodina Also called amoeba Also called amoeba They move and engulf their prey by producing limb-like extensions of their cytoplasm, called pseudopodia They move and engulf their prey by producing limb-like extensions of their cytoplasm, called pseudopodia One example is foraminifera One example is foraminifera

1c) Ciliates Phylum Ciliophora Phylum Ciliophora They are covered in hundreds of cilia, which allow them to move and sweep food particles to them for ingestion They are covered in hundreds of cilia, which allow them to move and sweep food particles to them for ingestion They are generally large and complex They are generally large and complex

1d) Sporozoans Phylum Sporozoa Phylum Sporozoa They are parasites They are parasites They form spores during their life cycle They form spores during their life cycle

1. Protozoa 1. Protozoa 4 types of locomotion 4 types of locomotion 2. Algae 2. Algae 3. Slime Moulds and Water Moulds 3. Slime Moulds and Water Moulds

2. Algae Simple, aquatic, chlorophyll-containing organisms Simple, aquatic, chlorophyll-containing organisms Range from single cells to giant seaweeds Range from single cells to giant seaweeds Greater than 2 billion years old Greater than 2 billion years old They are classified into 6 phylum based on their different types of chlorophyll and other pigments. (3 are mainly unicellular; 3 mainly multicellular). There are also differences in their cell wall chemistry, and form of food reserve in their cells. They are classified into 6 phylum based on their different types of chlorophyll and other pigments. (3 are mainly unicellular; 3 mainly multicellular). There are also differences in their cell wall chemistry, and form of food reserve in their cells.

2a) Green Algae Phylum Chlorophytes Phylum Chlorophytes Same type of chlorophyll and colour as most land plants Same type of chlorophyll and colour as most land plants Cell walls contain cellulose Cell walls contain cellulose Food reserves →starch Food reserves →starch Commonly found in fresh water and damp places on land Commonly found in fresh water and damp places on land Many of the unicellular organisms have flagella Many of the unicellular organisms have flagella

2b) Brown Algae Phylum Phaeophtyes Phylum Phaeophtyes They are generally all the multicellular marine organisms that we call seaweeds They are generally all the multicellular marine organisms that we call seaweeds Cell walls → cellulose and alginic acid Cell walls → cellulose and alginic acid Typically found in cold water Typically found in cold water

2c) Red Algae Phylum Rhodophtyes Phylum Rhodophtyes Typically found in warmer seawater Typically found in warmer seawater Able to grow at greater depths than other algae because their pigments are able to move through a greater distance in water Able to grow at greater depths than other algae because their pigments are able to move through a greater distance in water

2d) Diatoms Phylum Chrysopyhtes Phylum Chrysopyhtes The most abundant unicellular algae in the oceans The most abundant unicellular algae in the oceans They are a major food source at the base of marine and freshwater food webs They are a major food source at the base of marine and freshwater food webs Also a major source of atmospheric oxygen Also a major source of atmospheric oxygen Cell walls → rigid, silica Cell walls → rigid, silica

Diatoms: Sexual and Asexual Reproduction Asexual: the organism splits into two, each then grows a new half to fit inside the old one. The rigid cell wall cannot grow once it has been formed. Therefore, each generation of diatoms is smaller than the one before Asexual: the organism splits into two, each then grows a new half to fit inside the old one. The rigid cell wall cannot grow once it has been formed. Therefore, each generation of diatoms is smaller than the one before : reduction in size continues until now. The diatoms produce a zygote that grows to the original size before secreting a new cell wall. Sexual: reduction in size continues until now. The diatoms produce a zygote that grows to the original size before secreting a new cell wall. See Figure See Figure 12.32

2e) Dinoflagellates Phylum Pyrrophytes Phylum Pyrrophytes Unicellular, photosynthetic and mostly marine Unicellular, photosynthetic and mostly marine They have protective coats of stiff cellular plates They have protective coats of stiff cellular plates They are distinguishable because they have two flagella, one acts as a rudder and the other as a form of propulsion. They are distinguishable because they have two flagella, one acts as a rudder and the other as a form of propulsion. They are also an important food source They are also an important food source Reproduction is mainly cell division, they are capable of sexual reproduction Reproduction is mainly cell division, they are capable of sexual reproduction

2f) Euglenoids Phylum Eugenophytes Phylum Eugenophytes They also have two flagella but one is longer than other They also have two flagella but one is longer than other Over ½ do not have chloroplasts and are heterotrophs Over ½ do not have chloroplasts and are heterotrophs They could be autotrophic They could be autotrophic or heterotrophic

1. Protozoa 1. Protozoa 4 types of locomotion 4 types of locomotion 2. Algae 2. Algae different types of chlorophyll and different types of chlorophyll and other pigments other pigments 3. Slime Moulds and Water Moulds 3. Slime Moulds and Water Moulds

3. Slime and Water Moulds Like fungi they have spores Like fungi they have spores Like protozoa they glide from place to place and ingest food Like protozoa they glide from place to place and ingest food Like plants they have cellulose cell walls Like plants they have cellulose cell walls There are 3 groups: 2 groups of slime moulds and 1 group of water moulds There are 3 groups: 2 groups of slime moulds and 1 group of water moulds

3a) Water Moulds Phylum Oomycotes Phylum Oomycotes Most live as saprotrophs on dead organic matter Most live as saprotrophs on dead organic matter Others live as parasites on fish, insects and plants Others live as parasites on fish, insects and plants They differ from other fungus-like protists by the nature of their spores and their sexual life cycle They differ from other fungus-like protists by the nature of their spores and their sexual life cycle

3b) Plasmodial Slime Moulds Kingdom Myxomycotes Kingdom Myxomycotes They are visible to the naked eye. They are blobs called plasmodium, which contain many nuclei They are visible to the naked eye. They are blobs called plasmodium, which contain many nuclei They engulf their food They engulf their food They reproduce sexually where the plasmodium develops spore-bearing structures called sporangia. In dry periods spores develop and when damp conditions return the spores will germinate. The flagellae and the amoeboid cells fuse to make a zygote that will turn into a plasmodium They reproduce sexually where the plasmodium develops spore-bearing structures called sporangia. In dry periods spores develop and when damp conditions return the spores will germinate. The flagellae and the amoeboid cells fuse to make a zygote that will turn into a plasmodium

3c) Cellular Slim Moulds Phylum Acrasiomycotes Phylum Acrasiomycotes Exist as individual amoeboid cells with one nucleus each. Exist as individual amoeboid cells with one nucleus each. Feed on tiny bacteria or yeast cells, when there is no food a chemical is released which causes the cells to gather together in a pseudoplasmodium. Feed on tiny bacteria or yeast cells, when there is no food a chemical is released which causes the cells to gather together in a pseudoplasmodium. The pseudoplasmodium goes through the same reproduction as the plasmodial slime moulds. The pseudoplasmodium goes through the same reproduction as the plasmodial slime moulds. The two slime moulds are not suspected to be closely related The two slime moulds are not suspected to be closely related

Life Cycle of a Slime Mold