Protista, algae, and molds

1. Protista, algae, and molds biology

2. What is a protist? • A eukaryotic organism- membrane bound organelles • Can be multicellular or single • Can be autotrophic or heterotrophic • Many different forms of protists • Protozoa • Algae • Some are like fungi

3. Protozoa's • They are unicellular heterotrophs that feed on smaller organisms or dead matter • Grouped by how they move or paristic • Amoebas • Flagellates • Ciliates • sporozoans

4. Amoebas- • Belong to the phylum rhizopoda • Contain no cell wall and most move by pseudopodia, or false feet • They mainly live in oceans but can be found in freshwater • They diffuse nutrients through their cell membranes • Ocean dwelling amoebas are part of the plankton that live in the ocean • They can form hard shells around their membrane • Most amoebas reproduce by asexual reproduction • Where 1 parent can produce many offspring

6. Flagellates- a protozoan with flagella • They belong to the Zoomastigina phylum • They use 1 or more flagella to move around

7. Some can cause disease like the African sleeping sickness • Trypanosomabrucei • It is transmitted by flies, this is why fly nets when sleeping are so important • Causes issues with the nervous system, which causes people to sleep, and eventually die, unless treated

8. Others can be helpful, like the ones that live in termites • They break down the cellulose for the termite to get its nutrients. Without this protozoan, the termite would die

9. Ciliates- protozoan with cilia • Use cilia to move • Live in all types of aquatic environments • The paramecium is a ciliate • It uses the cilia to move food into its gullet • Most use asexual reproduction • Can undergo conjunction if times get rough

10. Sporozoans- parasitic protozoans • Produce spores- a reproductive cell that is not fertilized and produces a new organism • Contain 2 life stages • Trophozoite- the active feeding and growth stage • Cyst- or spore • Protozoans are in this group and can cause malaria and many other diseases • Toxoplasmosis- eating bad meat and vegetables, causes flu like symptoms • Giardia- an intestinal problem, caused by protozoans in untreated water that causes flu like symptoms • Malaria- kills millions

11. Malaria- caused by a sporozoan called Plasmodium that is transferred by mosquito bites • The parasite affects red blood cells and can cause death • This is why nets are so important, no bites, no problem

12. Algae • Protist that use photosynthesis are called algae. • They can use different pigments for photosynthesis, this causes different colors • Phytoplankton, a unicellular protist, is actually responsible for much of the oxygen that is produced

13. Algae are broken into 6 phyla • Euglenoids, diatoms, and dinoflagellates • These are mostly unicellular • Red algae, green algae, and brown algae • These are mainly multicellular

14. Euglenoids- unicellular • Most contain chlorophyll for photosynthesis • When there is no light, some can ingest food • They have 1 or 2 flagellum that allows them to get closer to light or food.

15. Diatoms- unicellular photosynthetic organisms that have a hard outer shell made of silica • Make up a large part of the phytoplankton population • The food they make is stored as oil instead of sugars. • This causes them to float near the surface, since oil is less dense than water • Diatoms can reproduce both sexually and asexually • Their hard shells can be used in industry for paints, abrasives, and pool filters-called diatomaceous earth

17. Dinoflagellates- • contain a cell wall made of cellulose, like plants, • they have 2 flagellum • they have a variety of pigments • Chlorophyll and carotenoids • Some produce toxins that can kill fish • Red tides are caused by dinoflagellates • They produce toxins that can kill • These toxins can be transferred to humans by eating • They thrive in the warm waters during the summer

19. Phylum Rhodophyta- Red Algae • Multicellular seaweeds • Red algae get the red color from pigments called phycobilins. They absorb the green, violet, and blue colors and therefore reflect the red color. • These colors can penetrate deep into the water, so red algae grow deep, around 100 meters down.

20. Thallus- the plant like structure of algae's • Different algae have different thallus arrangement • Thallus structure contains: • Hold fast- anchors algae to ground • Air bladder- allows the algae to float • Blade- leaf like structure

21. Brown Algae- phylum phaeophyta • Gets color from chlorophyll and yellow-brown pigments • Grows in cool waters around the world • Uses air bladders to get vertical to reach more sunlight • Kelp, a large and complex breed of brown algae can grow as large as 60 meters tall • They can form large forest like structures and become great ecosystems • Has many uses for humans

23. Green Algae- phylum Chlorophyta • Contains about 700 species and uses chlorophyll as main pigment • Mainly grows in fresh water • Found on trees, animals like the sloth, moist areas, and some in salt water • Can be either unicellular or multicellular • Chlamydomonas- a unicellular green algae • Spirogyra and Volvox are multicellular algae

24. Chlamydomonas • Volvox • Spirogyra

25. Algae reproduction • Asexually- like fragmentation, where the cell breaks apart and then starts replicating • Sexually- through the process of fusing gametes

26. Alteration of generationoccurs in all plants and some algae • Haploid form-single set of gene • Called a gametophyte because it produces male and female gametes • The gametes then fertilize to form a diploid zygote • The zygote then makes a new organism called a saprophyte • Diploid form- both sets of genes • Called a saprophyte. This develops into an adult • Adult then undergoes meiosis to produce haploid spores • The haploid spores then develop into gametophytes which starts the process over

28. Fungal like Protista • All are heterotrophic • Live in moist places with decaying matter

29. Slime molds • Plasmodium- acts as an amoeba by sliding around and eating decaying matter. • Can be made of thousands of nuclei • When times get hard, they produce haploid spores • Get carried away from the bad area • These spores will eventually form a new plasmodium

32. Water molds and downy mildews • Grow in moist places or in water • Feed on dead matter • Some are parasitic to plants • Water mold- form a white fuzz over its dead food • Eventually replicates and forms flagellated cells, something that a FUNGI WILL NEVER DO

34. Downy mildew- causes disease in potatoes • Caused Ireland to have a major food shortage and immigration to the states