Kingdom Protista Greek for “the very first” 200,000 species.

Kingdom ProtistaGreek 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 pseudopods- temporary projections of cytoplasm (oozing blob)

Have food vacuole-stores food

Unfavorable conditions- they become a cyst

Ex: Amoebas- binary fission, big blobs

Foraminiferans & Radiolarianshard 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=U7CoBXzJLWM

C. Ciliates- use cilia, fresh & salt waterEx: Paramecium- most common,

freshwater

Parts: Pellicle- outer membraneTrichocysts- 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-me-african-sleeping-sickness.html

Monsters Inside Me: Brain Eating Amoeba http://animal.discovery.com/videos/monsters-inside-me-the-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. Dinoflagellates- 2 flagella wrapped around them Asexual

½ photosynthetic, ½ heterotrophs

Luminescent- give off light

No histones for DNA to wind around

http://www.youtube.com/watch?v=eSROHwGaLCg

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- PhaeophytaChlorophyll 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- Chlorophytaact 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+famine&FORM=HDRSC3#view=detail&mid=C79162540736123451AEC79162540736123451AE

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