Notes 9-3 Protists What is meant by the word transport? Moving substances across the cell membrane

Kingdom Protista

Defining a Protist Protists are eukaryotic organisms that cannot be classified as animals, plants, or fungi Eukaryotic = has a nucleus Usually microscopic, usually unicellular What is the cell membrane made of? Lipids make it polar--> oxygen and co2 can readily pass through Small molecules can pass through protein pores

Defining a Protist Can be autotrophic or heterotrophic Move by cilia, flagella, or psuedopodia What is the cell membrane made of? Lipids make it polar--> oxygen and co2 can readily pass through Small molecules can pass through protein pores

Reproduction Asexually- Fission (binary, multi) Sexually- Conjugation What is the cell membrane made of? Lipids make it polar--> oxygen and co2 can readily pass through Small molecules can pass through protein pores

Animal-Like Protists Most are heterotrophic, moving around to capture prey Called protozoans Classified by how they move/live: pseudopods, cilia, flagella, parasites What is the cell membrane made of? Lipids make it polar--> oxygen and co2 can readily pass through Small molecules can pass through protein pores

Movement by Pseudopods “False feet” Uses cytoplasm to flow towards on end of cell to make it move to trap food Have contractile vacuoles to control water input/ output Example- Ameoba http://youtu.be/W6rnhiMxtKU

Ameoba

Movement by cilia Hairlike projections on protists that move with a wavelike motion to eat food Example- Paramecium

Paramecium

Movement by flagella Long, whiplike tail for movement to feed Protist lives in intestine of termite to digest wood = symbiotic relationship (mutualism because they both benefit) Giardia are protists found in streams that are harmful to humans (parasites)

Parasitic protozoans Have different types of movement: hosts, flagella, slime, etc. Plasmodium is a protist that causes malaria: mosquito bites an infected person and becomes infected with the plasmodium, then it takes it to the next human and infects a different human

Plant-Like Protists Most are autotrophic algae Some unicellular, some multicellular, some live in colonies Diatoms, Dinoflagellates, euglenoids, algae What is the cell membrane made of? Lipids make it polar--> oxygen and co2 can readily pass through Small molecules can pass through protein pores

Plantlike Protists The euglena is a common euglenoid that lives in fresh water. In sunlight, many euglenas can make their own food. Without sunlight, they obtain food from their environment.

Plantlike Protists Giant kelps are brown algae that have many plantlike structures.

Algal Blooms High temps and increase in nutrients (nitrates and phosphates) lead to increased algae populations Harmful to fish and humans (red tide)

Plant-Like Protists What is the cell membrane made of? Lipids make it polar--> oxygen and co2 can readily pass through Small molecules can pass through protein pores

Fungus-Like Protists Heterotrophic, have cell walls, use spores to reproduce Slime molds and Water molds and Downy Mildews What is the cell membrane made of? Lipids make it polar--> oxygen and co2 can readily pass through Small molecules can pass through protein pores

Slime molds Ooze along decaying materials eating bacteria and other microorganisms Small at first and use pseudopods to move, then join together to forma jellylike mass

Water molds and downy mildews Live in water or moist places Often look like tiny threads/ fuzz Cause of the potato famine in Ireland in 1845

Protists and the Environment Produce large amounts of OXYGEN Critical to marine FOOD WEBS Carbon Cycle Decomposition Symbiosis (corals, lichens, digestion)

Protists and the Industry Food Source (kelps and sea weeds) By products used in cosmetics, drugs, and gelatins Agar - polysaccharide from cell walls of red algae Diatom shells used as abrasive

Protists and the Human Health Malaria > caused by Plasmodium (apicomplexan) Sleeping Sickness > caused by protozoa > spread by tsetse fly Trichomoniasis > caused by Trichomonas vaginalis (mastigophoran) > one of the most common sexually transmitted diseases Discolored discharge, genital itching, the urge to urinate