Kingdom Protista Protists

Kingdom Protista The kingdom Protista includes eukaryotic organisms that don’t belong in one of the other eukaryotic kingdoms (Plantae, Animalia, or Fungi) These organisms share traits with these other groups; just not enough to be classified with them

Kingdom Protista Protists can be single- celled or multicellular organisms. All protists are eukaryotes. Groups of Protists: Protozoa (Animal-like) Algae (Plant-like) Fungus-like forms

Examples of Protists Includes: Amoebas Ciliates Flagellates Algae Amoeba, Naegleria fowleri Flagellate, Giardia lamblia Ciliate, Strombidium

Protozoans Protozoans: animal-like protists These protists share characteristics with animals such as: Feed on other organisms Cells lack cell walls Examples: A) Zooflagellates Move around using flagella B) Sarcodines Move using pseudopods (“false feet”) Amoebas C) Ciliates Move using cilia: short hair-like projections D) Sporozoans Do not move on their own Are parasitic Ciliate

Algae Algae: plant-like protists These organisms share characteristics with plants such as: Photosynthetic Cells contain cell walls Examples: A) Phytoplankton algae that live near the surface of the ocean. B) Red, brown or green algae C) Diatoms have silicon in their cell walls) Diatoms

Algae Besides oxygen production, algae are used by humans for many other purposes: A) Food seaweed & kelp are edible (Sushi anyone?) B) Production of agar Gelatin-like substance that has many uses C) Used to make toothpaste “pasty” D) Others?

Fungus-like Protists Like fungi, these are usually decomposers. Absorb nutrient from dead or decaying matter Fungus-like protists do not have chitin in their cell walls like true fungi do. Slime molds Water molds Slime Mold

Kingdom Fungi Fungi

Kingdom Fungi Eukaryotic organisms that primarily feed on dead or decaying matter. Grow on their food source Secrete enzymes that digest their food outside their bodies Absorb nutrients through their cell walls Can be multicellular (mushrooms, molds) or unicellular (yeasts)

Role of Fungi in Ecosystem Fungi are called “The Great Decomposers” Breakdown organic material and recycle it in nature Fungi also form mutualistic relationships with other organisms Ex: mycorrhizae Mutualistic relationship between algae and a fungus Algae makes food & fungus provides minerals

Characteristics of Fungi Fungal Structures Have cell walls, made up of chitin, a carbohydrate that also makes up the exoskeleton of insects. Hyphae: thin filaments that make up most fungi. Mycelium: many hyphae tangled together that help the fungus absorb food. Typically grow under the surface Fruiting Body: the reproductive structure of the fungus (Example: mushrooms)

Characteristics of Fungi Fruiting Body Fruiting Body Spores

Types of Fungi Mushrooms Molds Yeast Multicellular, most complex of fungi Molds Multicellular Not usually visible until fruiting bodies appear Yeast Unicellular, simplest form of fungi

Fungal Reproduction Reproduce both asexually and sexually. Asexual Reproduction: Hyphae break off and begin to grow on their own. OR, fungus produces spores that are released and can grow on their own. Mold spores

Fungal Reproduction Sexual Reproduction: Requires fungi of two different mating types, called either + (plus) or – (minus) When a + hyphae and a – hyphae meet, they fuse together. The fused hyphae grow and form a diploid zygote, which then will go through meiosis. Meiosis produces haploid spores, which are able to grow on their own.

Uses of Fungi Humans use fungi for a variety of purposes: A) Food Edible mushrooms, yeast (make bread) B) Food production Certain fungi can be used to flavor foods (ex: the “bleu” in bleu cheese C) Biotechnology D) Medicines antibiotics

Parasitic Fungi and Fungal Disease Most fungi that cause disease in humans are opportunistic pathogens, meaning they only infect people with weakened immune systems. Ex: athlete’s foot, ringworm, jock itch, etc. Most parasitic fungi infect insects and plants, many times killing their host.