Kingdom Protista
Greek for “the very first”
200,000 species
20-1 Kingdom Protista
• Any organism that isn’t a plant, animal,
fungus, or prokaryote
• Has a nucleus & membrane bound organelles
• Most are unicellular, some multi-cellular
• First eukaryotic organisms on Earth
• Can only grow & reproduce in wet
environments
• Found in Plankton- important food source for
others
• Feed mainly on bacteria
Lynn Margulis- hypothesis that
protists came from
mitochondria & chloroplasts of
prokaryotes that began to live
inside larger cells
Sub-divided by the way they
get nutrition, not based on
evolutionary history
20-2 Protozoans-animal-like
 A. Zooflagellates- swim using flagella
 Found in lakes & streams or inside other
organisms
 Absorb nutrients from decaying material
 Sexual & asexual reproduction
 Ex: Trichonympha- live in gut of termite
Trypanosoma- African sleeping sickness,
destroys red blood cells, spread by tsetse fly
 B. Sarcodines- use pseudopodstemporary projections of cytoplasm
(oozing blob)
Have food vacuole-stores food
Unfavorable conditions- they become a
cyst
Ex: Amoebas- binary fission, big blobs
Foraminiferans & Radiolarians
hard shells of calcium carbonate, food
source for marine environment, when
they die>build up chalk on ocean bottom
& cliffs
Cliffs of Dover- England
http://www.youtube.com/watch?v=U7C
oBXzJLWM
 C. Ciliates- use cilia, fresh & salt
water
 Ex: Paramecium- most common,
freshwater
 Parts: Pellicle- outer membrane
Trichocysts- defense structures
Macronucleus- multiple copies of
genes used for everyday
Micronucleus- reserve copy of all
genes
Gullet/oral groove-sweep algae &
bacteria to make food vacuole
Anal pore- removes waste
Contractile vacuole- expels excess
water
Ciliate reproduction
 Most are asexual
 Conjugation- exchange genetic
material with others
Line up side by side & swap
a pair of micronuclei
NO new individuals > Not
reproduction, just a sexual
process to exchange genes
& create genetic diversity
 D. Sporozoans- do not move on their own
Parasites
Sporozoites- transmitted through fluids
Ex: Plasmodium- causes Malaria
Carried by Anopheles mosquito,
infects liver, bursts red blood cells
 African Sleeping Sickness
http://animal.discovery.com/videos/monsters-inside-meafrican-sleeping-sickness.html
 Monsters Inside Me: Brain Eating Amoeba
http://animal.discovery.com/videos/monsters-inside-methe-brain-eating-amoeba.html
20-3 Plant-like Protists
 Have chlorophyll > photosynthesis
 Low amounts of light in sea, so they have
adapted and can use more than just red
light. Also, use accessory pigments
(carotenoids, xanthophylls)
Unicellular
 1. Euglena-
have 2 flagella, no cell wall
 Great swimmers, freshwater
 Eyespot- helps find light
 Can also live as heterotrophs
 Asexual
 Pellicle- outer membrane, allows to live in mud
 2. Dinoflagellateswrapped around them
2 flagella
 Asexual
 ½ photosynthetic, ½ heterotrophs
 Luminescent- give off light
 No histones for DNA to wind around
 http://www.youtube.com/watch?v=eSROHwGaL
Cg
3. Chrysophytes-
yellow green algae
 Gold colored chloroplasts
 Store food in the form of oil
 Sexual & asexual
 Form thread like colonies
4. Diatoms-
cell walls contain silicon (glass)
Extras
 Phytoplankton- does 70% of all the photosynthesis on Earth
 Symbiosis- lives in coral reef
 Algal Blooms- love growing in sewage
 Clean up waste but deplete water of oxygen, so kill off fish
 Ex: red tides http://www.youtube.com/watch?v=VKx-B0zLXu8
20-4 Multicellular Plant-like protists
 5. Red Algae- Rhodophyta- red plants
 Can live at great depths- great photosynthesizers
 Found from polar to tropical waters
 Lack flagella
 Stabalize coral reefs- coralline algae has calcium
carbonate in cell walls
6. Brown Algae- Phaeophyta
Chlorophyll a & c
Largest and most complex
Giant Kelp- over 60 m long
Contain a holdfast- anchors to bottom
or rocks
 http://www.youtube.com/watch?v=ZQb9ZFWfNZE
7. Green Algae- Chlorophyta
act as plants
 thought to be closely related to moss
Ex: sea lettuce
Bio I- Review terms
Diploid vs Haploid
Mitosis vs Meiosis
Body cells vs sex cells
Reproduction of Algae
 Alternation of Generations- switch between diploid &
haploid stages
 Chlamydomonas- mostly asexual- makes zoospores by
mitosis
 But during unfavorable conditions- sexual, releases + & gametes (haploid) that pair together to make a zygote
(diploid)
 Grows thick protective wall and when conditions are right,
becomes haploid again
Ulva- Sea Lettuce
 Diploid & haploid cycles are almost same
Human uses for Algae
 Food sources for oceans
 Earth’s oxygen from photosynthesis
 Sushi wraps, used to make ice cream,
salad dressings, pudding, plastics, paints
20-5 Fungus-like Protists
 Grow in damp areas
 Absorb food through membranes
 Have centrioles (fungi don’t)
 Lack chitin cell walls
Slime Molds
 Forest floors
 Cellular-cell membranes
 Acrasiomycota
 Most of life is free-living
 When conditions are bad > secretes chemical to form large
colony with nearby cells
 Colony migrates, makes fruiting body that produces spores
Acellular
 Myxomycota
 Known as plasmodia
 Many nuclei
 Mature sporangium > haploid spores
Water Molds- Oomycota
 Feed on dead or decaying matter in water or on plants on land
 Hyphae- cell walls of cellulose & motile spores
 Fungi don’t have
 Asexual- Zoosporangia (spore cases)
 Sexual- Antheridium- male nuclei, Oogonium- female nuclei
Facts
 Important recyclers of organic material
 Can be harmful- mildew, blights of grapes & tomatoes
 1840’s- potato #1 food in Ireland
 1845- Phytophora infestans = Great Potato Famine
 1.5 million migrate to US
Potato Famine
 Potato Famine
 http://www.bing.com/videos/search?q=great+potato+fa
mine&FORM=HDRSC3#view=detail&mid=C7916254073
6123451AEC79162540736123451AE
Protists
 Protists
 http://www.youtube.com/watch?v=-zsdYOgTbOk
 Plant-like
 http://www.youtube.com/watch?v=o5ESHXKGBvA
Summation video
 https://www.youtube.com/watch?v=Ln69k7LyTsU