Copyright Pearson Prentice Hall Bioluminescence http://www.youtube.com/watch?v=T2xh9-UPSlU http://www.youtube.com/watch?v=UXl8F-eIoiM Copyright Pearson Prentice Hall

20-3 Plantlike Protists: Unicellular Algae Photo Credit: Andrew Syred/Science Photo Library/Photo Researchers, Inc. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Plantlike protists contain chlorophyll and carry out photosynthesis. Copyright Pearson Prentice Hall

Chlorophyll and Accessory Pigments What is the function of chlorophyll and accessory pigments in algae? Copyright Pearson Prentice Hall

Chlorophyll and Accessory Pigments Chlorophyll and accessory pigments allow algae to harvest and use the energy from sunlight. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Euglenophytes Euglenophytes What are the distinguishing features of the euglenophytes? Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Euglenophytes Euglenophytes are plantlike protists that have two flagella but no cell wall. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Euglenophytes Pellicle Euglena Contractile vacuole Carbohydrate storage bodies Chloroplast Nucleus Eyespot Euglenophytes are plantlike protists that have two flagella but no cell wall. The green structures inside the euglena shown are chloroplasts, which allow the organism to carry on photosynthesis. Like paramecia, euglenas expel excess water through a contractile vacuole. Gullet Flagella Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Euglenophytes Two flagella emerge from a gullet in the cell. The longer of the flagella spins so it pulls the organism rapidly through the water. Euglenophytes are plantlike protists that have two flagella but no cell wall. Gullet Flagella Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Euglenophytes Near the gullet is a reddish pigment known as the eyespot, which helps find sunlight to power photosynthesis. Euglenas can also live as heterotrophs. Eyespot Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Euglenophytes Euglenas store carbohydrates in small storage bodies. Carbohydrate storage bodies Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Euglenophytes Euglenas do not have cell walls. Instead, they have an intricate cell membrane called a pellicle. The pellicle folds into ridges, each supported by microtubules. Pellicle Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Euglenophytes Euglenas reproduce asexually by binary fission. http://www.youtube.com/watch?v=5fg3Q-hbSsI . Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Plant-like Protists Phylum Chlyorophyta Green Algae – unicellular (Chlamydomonas) , colonial and multicellular (seaweed) Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Volvox Live in multicellular colonies, hence colonial. Some consist of 500 – 50 000 cells. Attached by cytoplasmic strands Copyright Pearson Prentice Hall

Ecology of Unicellular Algae Plantlike protists are important to freshwater and marine ecosystems because they make up the base of the food chain in many aquatic ecosystems. Copyright Pearson Prentice Hall

Ecology of Unicellular Algae Phytoplankton constitute the population of small, photosynthetic organisms found near the surface of the ocean. Phytoplankton carry out half of Earth’s photosynthesis. In addition, they provide nourishment for many organisms. Copyright Pearson Prentice Hall