Regular Biology Chapter 20 Waggy Kingdom: Protista Regular Biology Chapter 20 Waggy

Chapter Objectives… 1. Explain how protists are classified. 2. Discuss the key characteristics of the animal-like protists. 3. Discuss the key characteristics of the plant-like protists. 4. Discuss the key characteristics of the fungus-like protists. 5. Describe protist-caused diseases in humans.

Who are the Protists? Single celled eukaryotic organisms that do not fit in any other kingdom are called protists Most are microscopic but some algae can grow to be several meters long It is the most varied kingdom with animal-like, plant-like and fungus-like organisms It is thought that protists were the first eukaryotic cells on earth

How did Eukaryotic cells Develop? The Endosymbiosis Theory: The cell organelles, mitochondria & chloroplasts may have been free living protists at one time At some point they entered a cell and became a vital part of the cells metabolism: a cell organelle

Classification of Protists: They are classified by four main characteristics: 1. Body Structure 2. How they get food 3. How they move 4. How they reproduce

1. Body structure (all groups) Unicellular (single cell living alone) Colonial (many single cells living together) Multicellular (ONE organism made up of many cells)

2. Means of obtaining food Autotroph (plant-like) Heterotroph (animal-like) Parasitic (fungus-like) 3. Means of movement (animal-like) Pseudopodia Cilia (tiny hairlike structures) Flagella (long whip like structure)

4. Reproduction (all types) Binary fission Asexual reproduction Conjugation Sexual reproduction

Animal-like Protists… Domain: Eukarya Kingdom: Protista Phylum: there are four 1. Protozoa 2. Ciliophora 3. Sarcomastigophora 4. Apicomplexa

Phylum: Protozoa Means ‘first animal’ Most move using pseudopodia (‘false foot) The cell membrane extends outward & the cytoplasm fills it When enough cytoplasm has moved to the new area, the entire protozoa has moved An example of a protozoan is an amoeba

Phylum: Ciliophora Move by cilia that cover their bodies Are the most complex protists with many cell organelles Pellicle: clear layer of flexible protein that surrounds the cell membrane Mouth pore: opening where food is taken into the body Gullet: primitive stomach where food is digested Contractile vacuole: controls water balance