WHAT ARE PROTISTS? Chapter 14 Lesson 1
Essential Questions What are the different types of protists and how do they compare? How are protists beneficial?
New Vocabulary Protist Algae Diatom Protozoan Cilia Paramecium Amoeba Pseudopod
What are Protists? Protists are members of a group of eukaryotic organisms which have a membrane-bound nucleus. Share characteristics with plants, animals, and fungi but are not classified in any of these groups Most reproduce asexually Eukaryotic cells Can be plant-like, animal-like, or fungus-like Some are unicellular and some are multicellular
What are Protists?
Types of Plant-like Protists Diatoms – microscopic with a hard outer layer made of silica Dinoflagellates – unicellular protists that use 2 flagella to move, which cause it to spin Euglenoid – unicellular with a rigid cell coat (pellicle) and a flagellum Algae – photosynthetic protist that can be multicellular or unicellular Example: Volvox (unicellular)
Diatoms, Dinoflagellates, Euglenoid
Algae
Importance of Algae Provide food for animals and other animal-like protists Provide shelter for many aquatic organisms Help remove pollution from the water Pollution can be a food source for algae but this makes the population increase quickly This can cause red tides, which are toxic and cause many animals to die
Red tides
Types of Animal-like Protists Protozoans – resemble tiny animals Do not have chloroplasts or make their own food Live in wet environments Ciliates – protists that have cilia so they can move in the water Reproduce asexually, but they can go through conjugation Paramecium – protists with cilia and 2 types of nuclei Get food by forcing water through a groove on its side
Types of Animal-like Protists Flagellates – have more than one flagella Eat decaying matter Sarcodines – animal-like protists with no specific shape Amoebas – have an unusual adaptation for movement and getting nutrients Pseudopods – “temporary foot” Forms as the organism pushes part of its body outward
Paramecium
Flagellates and Sarcodines