Protists and Fungi Chapter 21 & 22
Dec 15, 2015
•Most diverse organisms
•Eukaryotic
• Mostly Unicellular Some multicellular
•Mostly Microscopic
•Asexual & Sexual Reproduction
•Heterotrophic (must eat) or
autotrophic (produce own food)
•Animal like - protozoans
•Plant like – algae – produce a large amount of worlds oxygen
Kingdom Protista – Chapter 21
Structures• Ectoplasm – thick cytoplasm• Pellicle – hard outer covering• Macronucleus and micronucleus• Contractile vacuole for
osmoregulation• Trichocyst – for protection• Gullet – food entry• Eyespot – sensitive to light• Chloroplast - photosynthesis
Besides a chloroplast, what protozoan
structure would be necessary for a
photosynthetic protist (also called algae)?
eyespot
Protozoan Diversity•Most species live in water•Grouped by method of movement
–Pseudopods – false feet; cytoplasmic extensions (amoebas)
–Flagella – whip-like tail (Flagellates)
–Cilia – small hairs (Ciliates)•Reproduction methods – look over
pgs. 462 & 463–Asexual & Sexual
Protozoan Diseases
Amoebic dysentery– Warm climates,
poor sanitation– Live in and destroy
intestines– Extreme diarrhea
filled with pus and blood, liver and brain lesions
• Plasmodium vivax– Malaria– In the saliva of the female
anopheles mosquito– Shaking, chills, fever, jaundice
(yellow skin), liver destruction, vomiting, seizures, blood in urine
Based on: Scientific American, June 1978
Adult Female Mosquito
Feeds on blood for protein to make eggs
Historic Efforts to Defeat Malaria
• Drained wetlands to reduce habitat for mosquito reproduction– But we lost important wetlands
• Control of mosquitoes using pesticides– But mosquitoes developed
resistance• Drugs (chloroquine) to protect
humans against infection by Plasmodium– But Plasmodium developed
resistance
• Trypanosoma brucei– African Sleeping Sickness– Tse-tse fly, wild animal reservoirs– Necrosis (tissue death) of lymph
tissue, nervous disorder
Overview of Kingdom Protista– Diversity – Most Diverse of all organisms– Live in moist or aquatic environments either free-living or
parasitic– Mostly unicellular, but some like kelp are multicellular– Some are photosynthetic others heterotrophic– Asexual and Sexual Reproduction– Grouped by methods of locomotion– Can be fungi-like, plant-like or animal-like (protozoans)– 1st eukaryotic cells – these characteristics, which are found
in many eukaryotes, first evolved in protist– Include: Algae, Amoebas, Diatoms, Dinoflagellates,
Euglenas, Paramecium, Sporozoans
Fungus – Chapter 22
• Eukaryotic• Spores• External digestion• Live in or on the host• Warm moist climates• Functions: decomposition, food
production, drug and antibiotic synthesis
• Oral or topical anti-fungals inhibit chitin formation
• Mostly a problem for immunocompromised
Fungal Structures• Thallas – body• Cell wall – made
up of chitin• Hyphae –
separated by septa
• Mycelium - mass of hyphae
• Fragmentation – breaking off part
Fungal Digestion
• Use hyphae• Release digestive enzymes• Food is dissolved outside of
fungi• Absorbed by mycelium
Fungal Diseases• Candida
– Yeast infections– Normal flora,
hospital pathogen– Head, hands,
genitals and mouth (thrush)
– White patches, itching, irritation, slimy layer, bread smell
They have a cell wall, which some antibiotics destroy.
Why would antibiotics
sometimes work on fungal
infections?
• Aspergillosis– Causes allergic reaction in body– Coughing up blood, weezing, weight
loss– Affects immunocompromised– Fungal balls in the lungs, surgical
removal– Dead leaves, compost piles
• Tinea– Cutaneous mycosis– Ringworm, athletes foot– Red ring like rash, itching,
peeling– Topical cream for most cases
Overview of Kingdom Fungi• Eukaryotic & Heterotrophic• Contain chitin• Obtain nutrients by secreting digestive enzymes and absorbing the
decomposed nutrients from their environment• Important resource recycler• Most reproduce by releasing spores that are produced asexually
and sexually• Exhibit nuclear mitosis – nuclear envelop remains through mitosis• Mostly multicellular,a few unicellular (yeast)• Filamentous bodies• Classified by reproductive structures• Some are harmful• Mutualistic relationships: Mycorrhiza – fungi & plant roots
Lichens- fungus & photosynthetic partner• Include: Mushrooms, Molds, Yeast