KINGDOM PROTISTA

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Transcript KINGDOM PROTISTA

KINGDOM PROTISTA
Overview
Cell number: Unicellular/Multicellular
 Cell type: Eukaryotic
 Nutrition: Autotrophs & Heterotrophs
 Habitat: Moist environments
 Divided into three types:
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animal-like
plant-like
fungus-like
Animal-like Protists
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Protozoa—single-celled microscopic
organisms that can move independently
Heterotrophic
Can be parasitic (live off other organisms,
cause disease)
Live most anywhere that moisture is
available
Protozoa
Can have three types of locomotion
(movement)
1. cilia—short, hair-like projections
2. flagella—long, whip-like “tails”
3. pseudopodia (“false feet”)—large, round
cytoplasmic extensions that help move cell.
They also surround and engulf food.
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Protozoa in the News
Calvin and Hobbes (Bill Watterson)
Types of Protozoa:
Amoebas
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Ameobas (Sarcodines)
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Use pseudopodia
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Shape constantly changes
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Live in fresh or salt water, soil
Amoeba engulfing a paramecium
Amoebas
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Can cause disease:
 Amoebic dysentery --spread by
contaminated food or water; causes severe
intestinal problems; can be fatal
Types of Protozoa:
Ciliates
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Have cilia
Ciliated protozoan
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Live in ponds, slow
moving streams
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Example:
Paramecium
Types of Protozoa: Flagellates
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Have 1 or more flagella
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Live in lakes, ponds
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Many are parasitic
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Ex: Giardia lamblia (intestinal parasite)
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Colonization of the gut results in inflammation and villous atrophy,
reducing the gut's absorptive capability. In humans, infection is
symptomatic only about 50% of the time, and protocol for treating
asymptomatic individuals is controversial.[4] Symptoms of infection
include (in order of frequency) diarrhea, malaise, excessive gas (often
flatulence or a foul or sulphuric-tasting belch, which has been known to
be so nauseating in taste that it can cause the infected person to
vomit), steatorrhoea (pale, foul smelling, greasy stools), epigastric
pain, bloating, nausea, diminished interest in food, possible (but rare)
vomiting which is often violent, and weight loss.[4] Pus, mucus and
blood are occasionally present in the stool. It usually causes
"explosive diarrhea" and while unpleasant, is not fatal. In healthy
individuals, the condition is usually self-limiting, although the infection
can be prolonged in patients who are immunocompromised, or who
have decreased gastric acid secretion.[4]
Types of Protozoa: Sporozoans
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Produce spores
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Many adult forms have no locomotion
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Many are parasitic, live in blood and tissue
of host
Sporozoans
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Ex: toxoplasmosis—why pregnant women
should not change litterboxes
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Plasmodium—causes malaria, spread by bite
of female Anopheles mosquito
Plant-like Protists: Algae
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Unicellular or multicellular ALGAE
Can be very large OR microscopic
Photoautotrophic, go through photosynthesis
Reasons why algae is not a plant:
– Lack organs (don’t have leaves, roots,
stems)
– Different type of reproduction than plants
Algae
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Phytoplankton—microscopic protists that
live in water
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Major source of food for ocean life
Major producer for food chain
Diatomaceous earth —when diatoms die,
they settle at the bottom of oceans. Build up
over time into layers. Material used as
abrasive in cleaning supplies and toothpaste
Unicellular Algae:
Euglena
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Have flagella
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Live in fresh water
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Contractile vacuole —gets rid of excess
water (hypotonic environments)
Euglena
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Very flexible (no cell wall)
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Usually photosynthetic, but can be
heterotrophic
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Has an eyespot—helps cell find light
Unicellular Algae:
Diatoms
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Photosynthetic
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Outer shells made of silica (glass-like
material)
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Release large amounts of oxygen
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Large component of phytoplankton
Unicellular Algae:
Dinoflagellates
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Small, usually unicellular
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Most photosyn., but can be heterotrophs
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Tend to be yellow, green or red
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Some are bioluminescent (glow)
Dinoflagellates
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Some produce “red tides”
– release a toxin that kills fish and
humans if we eat contaminated food
Multicellular Algae: Red Algae
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Ocean seaweed
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Live in deep waters
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Used as a food (nori)
Multicellular Algae: Green Algae
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Can be unicellular
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Most diverse group of algae
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Most live in fresh water, but can live in
oceans, soil
Green Algae
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Some are colonial (many cells living
together)
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Ex. Volvox
Multicellular Algae: Brown Algae
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Usually in salt water
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Large
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Ex. Kelp
Fungus-like Protists
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1st part of life cycle spent as an amoeba-like
organisms
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Later, they grow and look like a slimy,
white/yellow mold
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Can be seen without
microscope
Dog Vomit Mold
Fungus-like Protists
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Two types:
– slime molds
– water molds
Examples:
– white “fuzz” on dead fish/leaves
– Potato Blight that caused the Irish Potato
Famine
*THEY ARE ALL DECOMPOSERS*
Protists Reproduction
1. binary fission— asexual
2. conjugation— asexual
3. fragmentation—asexual; algae will break
into pieces and each piece grows into a
new individual
Reproduction: Alternation of
Generations
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Alternation of generation —life cycle that
alternates between a haploid and diploid
generation
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haploid—gametes (gametophytes)
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diploid—results from fusion of gametes
(sporophytes)
KINGDOM FUNGI
Overview
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Eukaryotic
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Can be uni- or multicellular
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Heterotrophic always (they absorb nutrients)
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Cell walls made of chitin (a tough
carbohydrate)
Structure
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Hyphae—hair-like filaments of fungi
that can group together to form larger
structures called mycelium (a cluster
of hyphae)
Structure
Uses of Fungi
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Decomposers for environment
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Make foods
– Edible mushrooms, truffles
– Bleu cheese
– Breads and alcohols are made with yeast (a
single celled fungus)
– Medicines (ex: antibiotic Penicillin)
Nutrition
Fungi release enzymes that break
down food outside of cells. Then, the
fungi absorbs the nutrients from their
surroundings
Obtaining Nutrients
1.
Saprophyte—lives on dead organic
(carbon-containing) matter
2.
Parasite—absorbs nutrients from
living cells
Obtaining Nutrients
3.
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Mutualistic—lives in a symbiotic (mutually
beneficial) relationship with another organism
ex: Lichens—organisms made of both an
algae (protist) and a fungus.
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Algae - provides energy through
photosynthesis
– Fungi - provides moisture/place to grow
Fungi Reproduction
Type of reproduction that a fungus has
is important in classification into
species
Fungus Reproduction
1. Asexually
A. Fragmentation—part of hyphae breaks off and
grows into a new mycelium
B. Budding—cells replicate their DNA, split into
two identical cells
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Ex: yeast
C. Spores—reproductive cells that can develop
into new organisms (are NOT true seeds, but they
act in a similar way)
Fungus Reproduction
2. Sexually
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Can happen occasionally
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When hyphae from two different fungi meet,
they can fuse together and make spores
that combine genetic info from both hyphae
Fungal Infections
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Human infections
– Can cause allergies/severe respiratory
illnesses
– Infect hair, skin, nails
 Athlete's foot, jock itch, and ringworm are
caused by the same fungus that can grow
in various locations
Fungal Infections
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Plants
– Some “blights” are caused by fungi
– Almost all chestnut trees have been
infected with a blight
More Examples
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Unicellular:
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Yeast (Sac fungus)
 Colonies resemble bacteria
 Are naturally occurring in humans, but when
growth gets “out of control” can cause yeast
infections
Multicellular
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Mushroom (Club fungus)