Eukaryotic Microbes. 3 Domains .

Eukaryotic MicrobesEukaryotic Microbes

3 Domains3 Domains

www.emc.maricopa.edu

5 Kingdoms5 Kingdoms

Protista *Fungi *AnimaliaPlantaeBacteria

www2.bc.cc.ca.us/bio16/1_Lecture.htm

What are some What are some characteristics of eukaryotic characteristics of eukaryotic

organisms?organisms?

Kingdom ProtistaKingdom Protista

Any eukaryote that is not an animal, plant, or fungus.

60,000 protist species.Most are single-celled.Include algae and protozoa.

Marine Protists

AlgaeAlgaeMany produce energy by photosynthesis.Most algal cell walls contain cellulose (also

found in plants).May be:

– Unicellular Diatoms Dinoflagellates Desmids

– Multicellular Large, plantlike seaweeds Include Red and Brown algae Euglena.

www.britannica.com

Unicellular AlgaeUnicellular AlgaeDiatoms

– Freshwater and marine environments.

– Cell walls contain silicon dioxide (glass).

– Used in filtration systems, insulation, and abrasives (like toothpaste).

www.rbgsyd.nsw.gov.au

Unicellular AlgaeUnicellular AlgaeDinoflagellatesUsually

photosynthetic.Some produce light

and are often called fire algae.

Responsible for “red tides.”

www.botany.hawaii.edu

www.botany.hawaii.edu

news.bbc.co.uk

Unicellular AlgaeUnicellular Algae Desmids

– Group of green algae.– Can photosynthesize.– Ex. Euglena

Has algal and protozoan characteristics.

Has a primitive mouth. Does not have a cell wall. Has an eyespot. Has flagellum.

– Ex. Spirogyra Filamentous algae.

Spirogyra. www.marietta.edu

Euglena. www.biologie.uni-erlangen.de

Multicellular AlgaeMulticellular Algae

Consists mainly of Brown and Red algae.

Brown Algae– Usually found in ocean

water.– Are a source of algin, which

is a thickener in ice cream. Red Algae

– Found in deeper ocean water than brown algae.

– One type of red algae (Gelidium) is the source of agar.

Red algae. Gelidium spp. www.canari.org

Brown algae. saltwater-aquarium-guide.net

ProtozoaProtozoaMost are

unicellular.Most are free-living

organisms that live in soil and water.

Ingest other organisms or organic material.

Do not have a cell wall.

www.marietta.edu

Protozoan Life CycleProtozoan Life Cycle

Usually have 2 stages to their life cycle.– Trophozoite

Motile, feeding, dividing stage.

– Cyst Dormant, survival

stage. www.tulane.edu

ProtozoaProtozoa

Symbiotic relationship– Between termite and

protozoan.

Parasitic relationships – Malaria– Giardiasis– African sleeping

sickness– Amoebic dysentery

A termite (top) next to a gut from another termite (middle). Contents (bottom) include spirochetes (arrows) and protozoa (P). animals.howstuffworks.com

Tsetse flies in the genus Glossina transmit the protozoan pathogens that cause African sleeping sickness (Trypanosoma gambiense and T. rhodesiense). www.cals.ncsu.edu

Protozoan ReproductionProtozoan ReproductionAsexual reproduction

– Binary fission produces 2 daughter cells.

– Schizogony Multiple nuclear divisions before cytoplasmic

divisions. Results in more than 2 daughter cells.

Sexual reproduction– Gametocyte production

2 haploid gametes which fuse to form a diploid zygote.

Protozoan ClassificationProtozoan Classification Based on method of

locomotion. Major groups

– AmoebaePseudopodia

– FlagellatesPossess flagella

– CiliatesPossess cilia

– Nonmotile protozoaCalled sporozoa

Amoeba. Naegleria

fowleri. classes.midlandstech.edu

Flagellate. Giardia

lamblia. www.pathobio.sdu.edu.cn

Cilate. Balantidium coli. www.tulane.edu Nonmotile. Plasmodium

vivax. www.dpd.cdc.gov

What is the world’s largest What is the world’s largest organism?organism?

Blue Whale

Giant Sequoia

Honey Mushroom, Honey Mushroom, Armillaria spp.Armillaria spp.

FungiFungi

Unicellular or multicellular eukaryotes. Reproduce asexually and sexually. 5 phyla

– based on their mode of sexual reproduction.

Lack chlorophyll. Have a cell wall made of chitin. Are saprophytes

– “garbage disposers” of nature.

Unicellular YeastUnicellular Yeast

3-8 µm in diameter. Found in soil and water and on skin of

many fruits and vegetables. Reproduce by an asexual process called

budding. Results in the production of a type of

asexual spore called a blastospore. Responsible for beer, wine, leavened bread. Some species are human pathogens (i.e.

Candida albicans).

Yeast cells budding. immunenhance.com

Multicellular FungiMulticellular FungiPossess hyphae

– A hypha is a tube-like cell.

A mass of hyphae forms a mycelium.

Septate hyphae have cross walls or septations.

Non-septate hyphae lack cross walls or septations.

Hyphal structure with septae. www.fungionline.org.uk

Multicellular Fungi ReproductionMulticellular Fungi Reproduction

Sexual or asexual reproduction.Can produce sexual or asexual spores.Sexual spores form by the fusion of 2

gametes.Asexual spores form in many different

ways.

Molds Molds Consists of many types of

multicellular fungi. Have great commercial

importance. Consists of many antibiotic

producing molds like Penicillium.

Used to make many different kinds of cheese.

Potato blight mold caused the famine in Ireland in the mid-19th century.

Penicillium, a genus of green mold, attacks many fruits and is the source of the antibiotic drug penicillin. www.britannica.com

Moldy bagel. www.sciencedaily.com

There are other types of fungi that are There are other types of fungi that are multicellular and are not considered multicellular and are not considered

microorganisms.microorganisms.

Fungi and DiseaseFungi and DiseaseAre responsible for

diseases in humans, animals, and plants.

In humans, infections could be superficial – affecting the skin, hair,

fingernails, toenails. Some of these fungal

infections can be more internal and thus be more severe.

Ringworm. Tinea corporis. www.research.usf.edu

Madura foot.

LichensLichens Mutualistic relationship

between an alga and a fungus. Are tough and self-sufficient. Can inhabit inhospitable

habitats such as deserts, newly formed volcanic islands, the Arctic, bare rock.

Grow slowly– Arctic colonies grow 1-2 inches

every 1000 years.– Some thought to be over 4000

years old.

Slime MoldsSlime MoldsHave both fungal

and protozoal characteristics.

May be cellular or acellular.

Found in soil and on rotting logs.

www.genome.gov

Slime MoldsSlime Molds

www.treknature.com

Cellular Slime MoldsCellular Slime Molds

Begin life as ameba-like organisms. If harsh conditions ensue, individual organisms

will fuse together to form a motile, multicellular form that is called a slug.

Slug becomes a fruiting body which consists of a stalk and spore cap.

Spores released and are airborne. If suitable habitat is found, a spore becomes an

ameba.

Acellular Slime MoldsAcellular Slime Molds

Also called plasmodial slime mold.Also produce a stalk and spores.Haploid cells fuse to form diploid cells.

– forms large masses of motile, multinucleated protoplasm.

The EndThe End