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Protists. What is a Protist?. The Protist Kingdom is also known as the “ Junk Drawer Kingdom”. THINK! What does this nickname imply about the kingdom? The organisms in this kingdom are so different from each other However, all protists do share 2 characteristics They all have a nucleus
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What is a Protist? • The Protist Kingdom is also known as the “Junk Drawer Kingdom”. • THINK! What does this nickname imply about the kingdom? • The organisms in this kingdom are so different from each other • However, all protists do share 2 characteristics • They all have a nucleus • They all live in moist surroundings
Protist Groupings • Because protists are such a diverse group, scientists group them into 3 different categories: • Animal-like Protists • Plant-like Protists • Fungus-like Protists • THINK! – What characteristics do you think all animal-like protists share? • All are heterotrophs and • can move from one place to another • THINK! – What characteristic do you think all plant-like protists share? • All are autotrophs • THINK! – What characteristics do you think all fungus-like protists share? • All are heterotrophs, have cell walls, and reproduce by spores
Animal-like Protists • Amoebas • Cell Structure: These are unicellular organisms. • Movement: They move with a pseudopod, meaning “false foot.” This is when the cell membrane fills with cytoplasm and pushes forward. They are known as shape shifters as they constantly change their shape by cytoplasmic streaming. • Nutrition: They eat bacteria and other small protists using pseudopods to surround, or engulf, the food into a new food vacuole. Excess water is controlled and expelled from an amoeba through a contractile vacuole. • THINK! - Are they heterotrophic or autotrophic? • Reproduction: Amoebas reproduce by binary fission.
Take a Look at an Amoeba’s Structure! • United Streaming Clip on Amoebas! • Monsters Inside Me – Brain Eating Amoeba - http://animal.discovery.com/videos/monsters-inside-me-the-brain-eating-amoeba.html
Animal-like Protists • Paramecium • Cell Structure: These are unicellular organisms that have an outer pellicle. • Movement: They move with tiny hairlike projections called cilia that cover the entire cell. Think of cilia as “tiny oars” that help to propel the cell forward. • Nutrition: Cilia sweep food such as bacteria and other small protists into the cell. Food is stored and digested in food vacuoles. • THINK! – Are paramecia heterotrophic or autotrophic? • Reproduction: Paramecia usually reproduce by binary fission but occasionally use conjugation to mix up the genes and increase genetic diversity.
Let’s Take a look at a Paramecium! United Streaming Clip on Paramecium! Paramecium Eating Pigmented Yeast http://www.youtube.com/watch?v=l9ymaSzcsdY&feature=related Paramecium in HD - http://www.youtube.com/watch?v=a4aZE5FQ284&feature=fvwrel
Plant-like Protists • Euglenoids • Cell Structure: These are unicellular organisms. • Movement: They move by using a flagellum. • Nutrition: They contain chloroplasts which capture sunlight and turn it into food. However, sometimes when there is no light, they must seek out their food. An eyespot senses light. • THINK! - Are they heterotrophic or autotrophic? • Reproduction: Euglenas reproduce by binary fission
Let’s look at the Structure of A Euglena • United Streaming Clip on Euglena! • Euglena Movement - http://www.youtube.com/watch?v=fI7nEWUjk3A • Euglena Under Microscope -http://www.youtube.com/watch?feature=endscreen&v=4MlR3dKfXmc&NR=1
Plant-like Protists • Diatoms • Cell Structure: These are unicellular with beautifull glass-like cell walls. Their shells are used in toothpaste, silver polish, pool filters etc. • Movement: They move by oozing chemicals out of their cell walls and then gliding gracefully over the slime on the surface of fresh or salty water. • Nutrition: They make their own food by capturing sunlight. • THINK! -Are they heterotrophic or autotrophic? • Reproduction: Diatoms reproduce by binary fission
Let’s take a look at Diatoms! • United Streaming Clip on Diatoms!
Plant-like protists • Algae (Green, Red, and Brown) • Cell Structure: Most green algae is unicellular. However, some green algae such as seaweed are multicellular. Red and brown algae are multicellular. • Movement: Most algae are anchored to rocks or are floating in fresh or salty water. • Nutrition: They make their own food by capturing sunlight. Green algae have a green pigment, red algae have a red pigment, and brown algae have a brown pigment. • THINK! - Are they heterotrophic or autotrophic? • Reproduction: Most reproduce sexually.
Let’s take a look at Simple Green Algae! • Refer to the diagrams on page 88! • United Streaming Clip on Simple, Unicellular Green Algae!
Let’s take a look at Simple Green Algae! • Refer to the diagrams in textbook! • Video Clip -Importance of Algae in the Environment
Fungus-like Protists • Water Molds • Cell Structure: Water molds grow as tiny threads that look like fuzzy coverings. • Movement: They are able to move at some point in their life. • Nutrition: Many feed off of crops such as potatoes, cabbages, corn, and grapes. Water molds led to the great Irish potato famine in 1845 that lead to over 1 million deaths of Irish people. • THINK! - Are they heterotrophic or autotrophic? • Reproduction: Most reproduce by spores. Spores are tiny cells that have the potential to develop into an entirely new organism.
Fungus-like Protists • Slime-Molds • Cell Structure: Slime molds are multicellular mass when they are clumped together as seen above. They are beautifully colored with many being a bright yellow. • Movement: They move in an amoeba-like way using pseudopods and oozing along the surfaces. • Nutrition: They feed on bacteria and decaying material. • THINK! - Are they heterotrophic or autotrophic? • Reproduction: Most reproduce by spores. • BEAUTY AND THE BLOB - http://www.nytimes.com/slideshow/2011/10/04/science/20111004-SLIME.html • Movies of Slime Mold (Princeton Univ) - http://www.youtube.com/watch?v=bkVhLJLG7ug