Kingdom Protista Section 9.4

Protists ~1.5 billion years old Eukaryotes Most: unicellular Membrane-bound nucleus More efficient at carrying out cellular activities than prokaryotes All of the eukaryotic organisms are here that do not fit into the other kingdoms Most: unicellular All single celled eukaryotes are protists Most: microscopic Autotrophs & heterotrophs Most: live in aquatic habitats (fresh or salt water) Plankton Zooplankton – animal-like Phytoplankton – plant-like

Classification of Protists Based on: How they obtain nutrition How they move Plant-like – AKA “algae” Animal-like – AKA “protozoa” (1st animal) Fungus-like – AKA “slime moulds”

Plant-like Protists 6 phyla Carry out photosynthesis Contain chlorophyll Can be unicellular or multicellular Commonly called algae

Unicellular Algae Four phyla Euglenophyta Chrysophyta (diatoms - pictured) Pyrrophyta (dinoflagellates) Some chlorophyta Accessory pigments (e.g. carotene) help absorb light, give algae a variety of colours

Euglenophytes Euglena Live in water Flagella for movement Photosynthesis in the light, but can consume solid food when light is unavailable Have an eyespot for sensing light

Chrysophytes Dinoflagellates

Red, Brown & Green Algae Mostly multicellular No tissues Green algae: phylum Chlorophyta Unicellular: phytoplankton Colonial: e.g.Volvox Multicellular: e.g. ulva, sea lettuce, spirogyra Green algae are primary producers Produce ~67% of the global supply of O2

Seaweed Red & brown alage Phaeophyta Rhodophyta Contain chlorophyll & other pigments to capture light that passes through water

Animal-like Protists “protozoans” Usually motile Most: reproduce asexually by binary fission Heterotrophic – must consume food Holozoic – engulf their food Saprozoic – absorb nutrients through their cell membranes Classified by how they move 4 phyla

Zooflagellates Phylum Mastigophora Move through water using flagella Most: parasitic

Sarcodines Phylum Sarcodina Move using cytoplasmic extensions called pseudopodia (false feet) Movement is also called “ameboid movement” Ex: amoeba

Amoeba The word “amoeba” means “to change” Their cytoplasm is always moving

Ciliates Phylum Ciliophora Protists that move using cilia ex: paramecium

Ameboid & Ciliated movement http://highered.mheducation.com/sites/0072919248/st udent_view0/chapter12/animations.html#

Sporozoans Do not move on their own Parasitic Move via the body fluids of their hosts

Parasitic Protists Vector – an organism that can carry a parasite – infects other organisms (hosts) with that parasite

Malaria Protist: Plasmodium Vector: Anopholes Mosquito 300-500 million cases each year 2-3 million deaths per year Fever, headache, vomiting Lives in the bloodstream, clogs capillaries, destroys blood cells

African Sleeping Sickness (Trypanosomiasis) Protist: Trypanosoma Vector: Tse Tse Fly Sub-Saharan Africa Fever, headaches, pain in joints Infects the central nervous system, causes confusion, lack of coordination, uncontrolled sleepiness

Giardiasis Protist: Giardia Transmission: Drinking contaminated water Severe diarrhea, vomiting Protist lives in the digestive tract

Questions Do developed countries have a responsibility toward treating and containing parasitic infections found in other parts of the world? Why is controlling the vector important to control the disease? One of the best ways to prevent many parasitic infections is to have a source of clean water. Why do you think many third world countries have more incidences of parasitic infection than other countries?

Fungus-like Protists Heterotrophs Decomposers Slime moulds and water moulds Leaves a slimy trail as it moves (slowly) across the ground Single cells come together to work as a primitive multicellular organism

To do: “Practice” questions on page 356-357 #1-11: in your notebooks #12: pass in on Friday Read Chapter 10, section 10.1-10.3 Kingdom Archaebacteria, Eubacteria & Protista quiz on Monday/Tuesday