kingdom protista biology 112
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KINGDOM PROTISTA Biology 112. Kingdom Protista. All are simple eukaryotes (cells with nuclei ). Protists are an unusual group of organisms that were put together because they don't really seem to belong to any other Kingdom Mostly microscopic Live in moist surroundings . - PowerPoint PPT PresentationTRANSCRIPT
KINGDOM PROTISTABiology 112
Kingdom Protista• All are simple eukaryotes (cells with
nuclei).• Protists are an unusual group of
organisms that were put together because they don't really seem to belong to any other Kingdom
• Mostly microscopic• Live in moist surroundings.• Most unicellular *(amoeba);
multicellular (seaweed/kelp)• Autotrophs, heterotrophs, or both.• Some can move - others cannot.
3 categories of Protists:
• Animal-like
•Plant-like•Fungus – like
Animal-like Protists (Protozoans)
*Unicellular heterotrophs*Four groups based on movement: those with pseudopods, cilia, flagella, and the non motile sporozoans.
Protozoans with Pseudopods Ex: Amoeba
• 1. Phylum Sarcodine• Pseudopods also
called ‘False Feet’ • Cell membrane pulls
in one direction & the cytoplasm folds into the bulge.
http://www.youtube.com/watch?v=7pR7TNzJ_pA
Amoeba
Mimivirus: infects a species of amoeba and is the largest known virus ever discovered.
Mimivirus enters amoeba cells by phagocytosis
Protozoans with cilia
EX: Paramecium2. Phylum – Ciliates• Cilia - hairlike structures - help
organisms move, get food and sense environment.
• Some unicellular, most are multicellular with 2 nuclei: one for everyday functions and one for reproduction
• http://www.youtube.com/watch?v=l9ymaSzcsdY&feature=fvw
Ciliates, cont.
• oral groove lined with cilia - moves H20 containing food into food vacuole at end of oral groove.
• food vacuole breaks down food and sends through cell.
• anal pore sends out waste.
Oral groove
Contractile
Vacuole
Food vacuole
food
vacuole anal pore
macronucleus
micronucleus
Paramecium
Protozoans with flagella3. Phylum zooflagelates• Use long whiplike part called
flagella to move. (one or two)• These usually live inside other
organisms
• Trichomonas vaginalis: an STI
Non Motile Protozoans4. Phylum Sporazoa - parasites
• Feed on cells & body fluids of host
Sporozoans like plasmodium (causes malaria) feeds off liver and blood cells
Plantlike Protists
• Better known as algae • Autotrophs (photosynthesis)• Size: unicellular to very large• Contain different pigments so
they come in different colors.• Algae perform 55-75% of all
photosynthesis on Earth so it provides most of the world’s oxygen!
• Ex: colonial volvox
White cliffs of Dover are white from plant-like protist shells
Kelp forests
Funguslike Protists
• Funguslike protists are heterotrophs that absorb nutrients from dead or decaying organic matter (decomposers/saprobes)
• Ex: slimemold, watermolds
Examples of slime molds
Funguslike Protists cont…
• Land-dwelling water molds cause a number of plant diseases, including mildews and blights.
• A water mold Phytophthora infestans was responsible for the Irish Potato Famine of the 1845-1848
Parasitic Protists
Biology 112
Parasitic ProtistsParasite: an organism that lives off of a HOST
organism (either on it or in it) and causes harm to the host.
Vector: an organism that carries parasite, and can transfer the parasite to another organism.
Parasite Vector Host
MALARIA
Protist – PlasmodiumVector – Female Anopheles Mosquito
• 4 species of protozoans that carry malaria but Plasmodium falciparum is especially deadly
• http://www.youtube.com/watch?v=JwsoK8O0lXE
Vector / Protist?
Liver
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Liver cell
Female Anopheles mosquito – site of sexual phase of plasmodium
Plasmodium sporozoites infect liver cells and reproduce asexually
Merozoites reproduce asexually in RBC’s
Red Blood CellsRed blood cell bursts and merozoites infect more RBC’s
Malaria
• WHO: 300-500 million cases/year• 1.5-2.7 million deaths/year (more than AIDS)
• Symptoms: fever, headache, vomiting and other flu-like symptoms
• The protist lives inside the bloodstream eventually clogging capillaries and destroying blood cells, leading to death if untreated.
• http://www.youtube.com/watch?v=JwsoK8O0lXE
Giardiasis• Protist - Giardia• Infects ~ 200 million people worldwide
• Transmission: contaminated water (outdoor streams, other untreated water sources); day-care environments (fecal-oral route)
• Takes up residence in the digestive tract.
• Symptoms: severe diarrhea and vomiting.
Giardia
African Sleeping Sickness
• Protist – Trypanosoma• Vector – Tse Tse Fly
African Sleeping Sickness• Occurs mostly in sub-saharan Africa
• Initial symptoms: fever, headaches, pain in joints
• Infects the CNS: causes confusion, lack of coordination and uncontrolled sleepiness.
• Leads to death if left untreated.• http://www.youtube.com/watch?v=4aVUrGO97Zg