Kingdom Protista Chapter 21

What are Protists? Protists are eukaryotes that are not members of the Kingdoms: Plantae, Animalia, or Fungi Protists are generally unicellular Protists can be heterotrophs, autotrophs, or decomposers

Classification Protists are a very diverse groups of organisms Different groups of Protists evolved independently from archaebacteria Protists are generally classified by the way they obtain food. There are three main categories of Protists Animal-like (Protozoa) Plant-like (Algae) Fungus-like

Animal-Like Protists (Protozoans) Classified by their method of movement. There are four phyla of Protozoans Zooflagellates Sarcodines Ciliates Sporozoans

Zooflagellates Animal-like Protists Use Flagella to move Absorb food through their cell membrane Live in lakes, streams, and inside other organisms

Form the basis of many food chains Asexual reproduction by means of binary fission Ex. Giardia- water borne protozoa that causes severe intestinal distress Trichonympha –helps termites digest wood

Sarcodines Animal-like Use pseudopods for feeding and movement Asexual reproduction by means of binary fission Ex. Amoeba

Ciliates Use Cilia for feeding and movement Cilia- short hairlike projections Found in lakes, streams, and oceans

Use self-defense mechanisms known as a trichocyst Reproduce by binary fission and conjugation Ex. Paramecium

Sporozoans Do not move on their own Considered parasites Complex life cycle, involve more than one host Reproduce by sporozoites Attach to host, penetrate it, and live within it Ex. Pneumocystis carinii. – causes pneumonia in AIDS patients Plasmodium vivax – causes malaria

Diseases Some animal-like protists cause serious diseases, including malaria and African sleeping disease Malaria 300-500 million people suffer from Malaria 2 million die each year Plasmodium causes malaria Female Anopheles Mosquito is the carrier

Malaria Life-cycle

Other Diseases Toxoplasmosis [Toxoplasma gondii] - Caused by eating raw meat - May become infected through the handling of cat litter boxes - Symptoms are similar to the flu. - Especially hazardous to pregnant women, may cause eye damage in the fetus

More Diseases African Sleeping sickness Amebic Dysentery Fatal Caused by the bite of a tsetse fly Amebic Dysentery Causes severe diarrhea

Plantlike Protists Contains green pigment chlorophyll Carries out photosynthesis Highly mobile

Euglenophytes Plantlike Two flagella Has eyespot Helps find sunlight No Cell Wall, but has a pellicle Ex. - Euglena eyespot

Dinoflagellates Can be both heterotroph and autotrophs, some are both at the same time Two flagella – causes to move in a spiral motion Asexual reproductions by binary fission

Red Algae Able to live at great depth due to their efficiency in harvesting light energy Contain Chlorophyll a and phycobilins ( absorb blue light) Multicelluar Lack flagella

Brown Algae Contains Chlorophyll a and c as well as fucoxanthin Largest and most complex Multicellular Mostly found in shallow coastal water Ex. - Kelp

Green Algae Have chlorophyll a and b Store food in the forms of starch Very similar to plants Contain cellulose in their cell wall

Human Uses of Algae -Often rich in vitamin C and iron Medicine -treat stomach ulcers, arthritis, and high blood pressure Food -ice cream, salad dressing, pudding, candy bars, pancake syrups, and eggnog Industry -chemicals from algae are used to make plastics, waxes, transistors, deodorants, paints, lubricants, and even artificial wood Science laboratories -Remember Agar!!!

Fungus-like Protist Like fungi, fungus-like protist are heterotrophs that absorb nutrients from dead or decaying organic matter Unlike fungi, fungus-like protist have centrioles

Slime Molds Recycle organic matter Closely resemble amoebas Multi-cellular

Fungi - Chapter 21

The Kingdom Fungi Fungi are eukaryotic heterotrophs that have cell walls. These cell walls are made of chitin

The bodies of multicellular fungi are composed of many filaments called hyphae

Fungi Reproduction Most fungi reproduce both asexually and sexually The cells or hyphae may break off and begin to grow on their own. Some fungi produce spores. This is a form of asexual reproduction.

Spores are Asexual

Fungi Classification Over 100,000 species. Grouped according to their structure and method of reproduction. Four main groups: Molds, Sac Fungi, Club Fungi and Imperfect Fungi

Molds - Phylum Zygomycota Has both a sexual and asexual phase in its life cycle Produces spores on structure called sporangia Example: Bread Mold

Bread Mold

Sac Fungi Phylum Ascomycota Both a sexual and asexual phase in it’s life cycle Produces spores on structure called asci which form on the inside of the cup Examples: Yeast Morels

Yeast

Morels

Morels

Club Fungi Phylum Basidiomycota Both a sexual and asexual phase in its life cycle Produces spores on structures called basidia Basidia are found on the gills that grow on the underside of a mushroom cap

Club Fungi (con’t.) Includes many edible and poisonous varieties Examples: Button, Portobello and Shitaki mushrooms

Club Fungi

The Imperfect Fungi Phylum Deuteromycota No sexual phase of their life cycle has been observed. Example: Penicillin

Penicillin

Ecology of Fungi Fungi are found in all ecosystems in all environments on Earth All fungi are heterotrophs They cannot move to capture food, but their mycelia grow into the tissues and cells of organisms. Many are saprobes, which obtain food from decaying organic matter Some are parasites Some are symbionts

Fungi as Decomposers Fungi recycle nutrients by breaking down the bodies and wastes of other organisms. Without fungi and other decomposers, energy-rich compounds would forever be trapped in the bodies of dead organisms. If these materials were not returned, the soil would quickly be depleted, and Earth would become lifeless.

Fungi as Parasites Some fungi cause tremendous losses of food and crops. A few fungi cause human disease. Example: ringworm, athletes foot fungus, yeast infections.

Ringworm

Athletes Foot Fungus

Symbiotic Relationships Some fungi form symbiotic relationships in which both partners benefit. Lichen: An association between a fungus and a photosynthetic bacteria or algae. Lichens are often pioneer species

Lichens

Mycorrhizae: a mutualistic relationship between a fungus and a plant Mycorrhizae: a mutualistic relationship between a fungus and a plant. The fungus supplies the plant with water and minerals. The plant supplies the fungus with sugars from photosynthesis

Micorrhizae