Download 19-2 Protist Diversity Autotrophic protists

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19-2 Protist Diversity
Autotrophic protists- also known as algae. Characterized by
unique cell walls (algin)
Serve same function in marine environment as plants do in
terrestrial environment- photosynthesize, base of food pyramid
Defn- Plankton Algae, bacteria, and animals found near the
surface of fresh- or saltwater.
Phytoplankton (phyto- plant) photosynthetic plankton
Zooplankton- (zoo- animal) heterotrophic plankton
Unicellular algae are phytoplankton. Includes Euglenophyta,
Chrysophyta, Dinoflagellata, many Chlorophyta
Multicellular algae- brown (Phaeophyta), most red
(Rhodophyta), some green (Chlorophyta).
Heterotrophic- several groups
Fungi-like- slime molds (Myxomycota, Acrasiomycota), water
molds (Chytridiomycota, Oomycota) are decomposers, found
in wet areas.
Parasitic- Mastigophora (Trichonympha – in termites), Opalinida
(intestinal parasites), Sporozoa (Plasmodium)
Animal-like – Sarcodina (amoeba), Ciliophora (Paramecium)
For next time- 10 section review questions from 19-2.
19-3 Protist Diseases
Protists cause human diseases!
Mainly transmitted by contaminated water, insects
Example- Plasmodium parasite causes malaria, kills more than 1
million people a year.
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Life cycleWhen mosquito bites an infected person, Plasmodium
gametes are taken into the mosquito’s stomach.
Gametes unite to form a zygote, which matures and
produces spores.
Spores migrate to mosquito’s salivary glands.
Plasmodium spores are injected into bloodstream by female
mosquito.
Migrate to liver, reproduce, release spores into bloodstream
Spores invade red blood cell, divide, forming gametes and
destroying the blood cell.
When bitten by mosquito, the cycle repeats.
Death often comes to the host, sometimes by loss of blood cells,
sometimes by opportunistic infection.
What to do?
To avoid infection, kill mosquitoes. Problems- mosquitoes
develop resistance, DDT mostly outlawed
To treat the infection, quinine and derivatives. Problems –
Plasmodium develops resistance, varies surface proteins
Approximately 20% of the population of the undeveloped world
has been infected by Protist diseases such as dysentery,
sleeping sickness, and malaria.
For next time:
Test, Packet
19-3 Section Review- 5 questions
Chapter Review- 2-7, 10, 13, 15, 19, 20. XC- 29
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