Transcript Protists and Fungi

Protists and
Fungi
Chapter 21 & 22
Kingdom Protista – Chapter 21
•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
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
What common function
do pseudopodia, cilia,
and flagella share in
protozoa?
movement
How do multicellular
algae differ from
plants?
they do not have
roots, stems, or
leaves
Amoebas pseudopods
Paramecium
- cilia
Trypanosomes - flagellates
Plasmodium
spore formers
Algae: Green, Red & Brown
Photosynthetic
Diatoms
unicellular, photosynthetic unique double
shells made of silica, move by gliding
Stentor
Vorticellacilia
amoeba
euglena
paramecium
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
Adult Female Mosquito
Feeds on blood for
protein to make eggs
Based on: Scientific American, June
1978
Distribution of Malaria
Based on: U.S. News & World Report, January 1997
Risk of Malaria: 1946, 1966 & 1994
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
• Leishmania
– Carried by sand flies, rodent reservoirs
– Tropical disease
– Severe skin lesions
• 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
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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
Why would antibiotics
sometimes work on
fungal infections?
They have a cell
wall, which some
antibiotics destroy.
• Aspergillosis
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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
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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