Transcript Protists: Plant-like Protists and Fungus

Protists:
Plant-like Protists and
Fungus-like Protists
Plant-like Protists
• Unicellular or Multicellular?
– Both!!
• Autotroph or Heterotroph?
– Autotroph!!
– Uses Chlorophyll or Accessory Pigments
• To make their own food
• Where do they live?
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Soil
The barks of trees
Fresh water
Salt water
Plant-like Protists
• How are they divided into Phyla?
– Number of cells and complexity
• We will learn about six groups.
– Euglenoids
– Diatoms
– Dinoflagellates
– Red Algae
– Brown Algae
– Green Algae
Plant-like Protists
• Euglenoids are green, unicellular algae
that are found mostly in fresh water.
• Unlike other algae, euglenoids can be
heterotrophs under certain conditions
Plant-like Protists
• Diatoms
– Diatoms are unicellular protists
– Some float on the surface of freshwater and saltwater
– Others attach to objects such as rocks in shallow
water.
– Diatoms move by oozing slime out of slits in their cell
walls.
– Cell walls of dead diatoms are used to make
toothpastes and household scouring products as well
as in swimming pool filters and insecticides.
Plant-like Protists
• Dinoflagellates
– Dinoflagellates are unicellular algae covered by stiff
plates that look like a suit of armor.
– Dinoflagellates exist in a variety of colors.
– All dinoflagellates have two flagella
– Can be the cause of a Red Tide
• Red Tide - red tides occur most often when there is an
increase in nutrients in the water
• Red tides are dangerous when the toxins that the algae
produce become concentrated in the bodies of organisms
that consume the algae
Plant-like Protists
• Red Algae
– Almost all red algae are multicellular
seaweeds.
– Red algae growing at depths greater than 260
meters.
– Carrageenan in Red algae is used in products
such as ice creams and hair conditioners.
– For people in many Asians cultures, red algae
is a nutrient-rich delicacy that is eaten fresh,
dried, or toasted.
Plant-like Protists
• Brown Algae
– Brown algae contain brown green, yellow, and orange pigments.
– Holdfasts anchor the alga to rocks.
– Stalks support the blades, which are the leaflike structures of the
alga.
– Brown algae also have gas-filled sacs called bladders that allow
the algae to float upright in the water.
– Brown algae flourish in cool, rocky waters.
– The giant kelps form large underwater “forests” where many
organisms, including sea otters and abalone, live.
– Some people eat brown algae for their nutrients and can be
found in foods such as puddings and salad dressings.
Plant-like Protists
• Green Algae
– All green algae contain green pigments.
– Most green algae are unicellular, some form
colonies, and a few are multicellular.
– An example is green seaweed, washed up on
a beach.
– Most green algae live in either freshwater or
saltwater surroundings.
– Few live on land and are found along the
bases of trees or in moist soils.
Plant-like Protists
• Saltwater algae bloom versus a freshwater
algae bloom
– Both are a rapid increase in algae growth due
to an increase in nutrient in the water
– Saltwater?
• Red Tide
– Freshwater?
• Eutrophication
– nutrients such as nitrogen and phosphorus build up in a
lake or pond over time, causing an increase in the growth
of algae.
Plant-like Protists
• Why is eutrophication bad?
– Nutrient increase
– Algae increase too much
– Algae then dies
– Bacteria break down algae
– To breakdown all the algae bacteria use up a
lot of oxygen
– Not enough oxygen for fish and other animals
and they die
Fungus-like Protists
• Why Fungus–like?
– Have cell walls like fungus
– Decomposers like fungi
– Reproduce with spores like fungi
Fungus-like Protists
• Why not fungus then?
– Fungus like protist are able to move at some
point of their life cycle.
– True fungi do not move!
Fungus-like Protists
• Three types of Fungus-like protists.
– The three types of fungus-like protists are:
• water molds
• downy mildews
• slime molds
Fungus-like Protists
• Water molds and downy mildews
– Live in water and moist places
– grow as tiny threads that look like a fuzzy
covering
• What do they do?
– attack food crops, such as potatoes,
cabbages, corn, and grapes
– Cause of Irish potato famine
Fungus-like Protists
• Slime Molds
– live in moist soil and on decaying plants and
trees (fallen logs , dead leaves, forest floors).
– Slime molds are often beautifully colored.
– They move like an amoeba forming
pseudopods.
– Slime molds feed on bacteria, other
microorganisms and decaying matter.
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What is it?
What is it?
What is it?
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