Advanced Life Science Rainier Jr/Sr High School Mr Taylor

Kingdom Protista A very diverse Kingdom An organism is placed in this kingdom because it is eukaryotic and isn’t an animal, plant, or fungus. Most are unicellular All are eukaryotic

Kingdom Protista 3 major groups of Protists exist Algae; the autotrophic, photosynthetic protists Slime molds; heterotrophic fungus-like protists Protozoa; heterotrophic animal-like protists

Protozoa Proto means “first” and zoa means “animal”, so protozoans are the first, simplest organisms to exhibit animal-like traits They are eukaryotic They are heterotrophic and usually consume other micro-organisms (rather than absorbing dissolved nutrients) Most live in or near water Marine and freshwater forms Upper layers of moist soil Plant and animal tissues

Protozoa Four phyla are considered protozoan and are classified by their method of locomotion. 1. Mastigophora/Zoomastigina: move by flagella 2. Sarcodina/Rhizopoda: move by pseudopods 3. Ciliophora: move using cilia 4. Sporozoa/Apicomplexa: are non-motile

Mastigophora/Zoomastigina Move using flagella Many are parasites, some are mutualistic Trypanosoma spp cause encephalitis (“sleeping sickness”) in people, common in Africa. Is carried by the tsetse fly. (A parasite) Trichonympha spp live in the digestive tract of termites and digest cellulose (wood). (A mutualistic relationship)

Sarcodina/Rhizopoda Move using pseudopods (pseudo means “false” and pod means “foot”), an extension of the cytoplasm. The most common protozoans in this group are the amoeba (shape-shifters) Amoeba in motion Amoebas have many complex structures and activities A contractile vacuole: gets rid of excess water. Eats by phagocytosis

Sarcodina/Rhizopoda Move using pseudopods (pseudo means “false” and pod means “foot”), an extension of the cytoplasm. The most common protozoans in this group are the amoeba (shape-shifters) Amoeba in motion Amoebas have many complex structures and activities Reproduce by binary fission Becomes a “cyst” to prevent death during dry conditions

Sarcodina/Rhizopoda Move using pseudopods (pseudo means “false” and pod means “foot”), an extension of the cytoplasm. The most common protozoans in this group are the amoeba (shape-shifters) Amoeba in motion Amoebas have many complex structures and activities Are detritovores often (eat rotting foods) but also will eat other protists and bacteria Are common in ponds and areas with lots of sludge

Sarcodina/Rhizopoda Move using pseudopods (pseudo means “false” and pod means “foot”), an extension of the cytoplasm. The most common protozoans in this group are the amoeba (shape-shifters) Amoeba in motion Amoebas have many complex structures and activities Have a photosensor and move away from light. This trait is called negative phototropism. Have chemosensors to detect food and harmful substances.

Ciliophora Cilia are short, hair-like extensions from the cell membrane. They are usually plentiful and move in a coordinated, wave-like fashion. This action serves to either propel them through a medium or moves food particles past themselves. Some move through a liquid medium and are “motile”. Some attach to a substrate (like a rock or a leaf) and are called “sessile”

Ciliophora The most common ciliate is the Paramecium spp. This is also a very complex unicellular organism. Has a “head” and “tail” Eats by diffusion and also by sweeping food into an oral groove and mouth pore. Food is digested in a food vacuole and undigested remains are eliminated through an anal pore. This forms a rudimentary digestive system.

Ciliophora The most common ciliate is the Paramecium spp. This is also a very complex unicellular organism. They display an avoidance reaction when they run into something. They can shoot out little barbed “hairs” that can deter predators and help capture prey. Paramecium Video

Sporozoa/Apicomplexa All sporozoans are non-motile parasites and are carried around in the blood or tissue fluids of their hosts. They often have complex life cycles involving several hosts. Plasmodium spp cause malaria in people. The life cycle involves mosquitoes and people. Neorickettsia salmonicola causes “salmon disease” in dogs. It’s life cycle involves snails, salmon, and dogs.

Sporozoa/Apicomplexa Plasmodium spp in human red blood cells Ricketssia spp in the lining of the digestive tract of a horse