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Multicellular Protists
*Rhodophyta* - tropical regions
Phaeophyta
Chlorophyta ——> Chlorophyceae
Ulvophyceae
Charophyceae
Heterotrophs
Rhodophyta
• Chl a phycobilins
• Sulfonated polymers (agar caragreenan)
• Floridean starch
• Zygotic and Sporic Meiosis
• The multicellular protists are all related to algae but not very closely related
Rhodophyta
• They generate large quantities of sulfonated polymers like agar
...

• Because these things are multicellular- issues with sex
...
There is another type that is usually
used known as the Gametic
...
Unicellular method of sex is
by conjugation
...
2 haploids fuse together to form a diploid form and then that
undergoes meiosis quickly to regenerate the haploid form and will go on
to become multicellular organisms
...
The haploid forms a multicellular individual and the
diploid undergoes meiosis that creates the haploid cell
...
(Multicellular organisms are both haploid and diploid)
...
*Haploid and diploid are multicellular* In a diploid state you have

two copies of everything
...

• Gametic Meiosis- *Diploid is multicellular*
• When you have uv light, it hits oxygen and splits it and eventually you’ll get an
ozone that protects us from uv light
...
—>
Multi cellular forms of sex [three forms]
Phaeophyta
• One of the examples of a heterokont and to some extent can be related
amongst the heterkonts in the unicellular organisms
...
reason that its
brown is because it has the carotenoid fucoxanthin that provides them
with the brown colour
...

When you’re in an aqueous env there are a couple ways you can grow
...
Tide going in and out near coastal
regions are the nutrients supplied from land
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They are also photosynthetic
organisms and will grow up with a stipe and near the surface it will
branch out and form blades
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100 m is a normal height for these plants
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Maximum amount of light present there
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In a cross section will see cells that are basically lined up one on
top of the other creating a conductive tube to pass down food or
photosynthetic products
...
Important in the creation of multicellular structures where you
require transport from one place to the other
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• They engage in gametic meiosis and also spark meiosis
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• When people initially thought about them they divided them into 3 groups
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There are
similarities between the two of them
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If you have two cells dividing you get this furrow between the
two cells where they will pinch and create two different new cells
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Occurs in Chlorophyceae which is marine and
aqueous
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Microtubules play a role here as well because when you separate the two
nuclei you will have microtubules that are present as well
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This type of mechanism is also seen in higher plants
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Ulvophyceae
• The Ulvophyceae is in between the two and have other traits that are different
from the other two
...
Ulva- Sea lettuce will
be either haploid where you’l get gametes that will form and create
organisms that are diploid when they fuse
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• This particular organism is small
...
One that is
very common in scientific research is known as Acetabularia
mediterranea
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• The organization of the Siphonous Algae in particular the Acetabularia
mediterranea are the rhizoids that hold it to the bottom of the pool, the
long stalk
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It will
grow up and will form cysts at the top that will release motile stuff for
sexual stuff
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Have the
stalk, the cap formation on the top
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All this time in this process, nucleus
remains at the base
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Nuclei
were transplanted into enucleated rhizoid fragments
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• How could the cap regenerate without the presence of DNA in Acetabularia
mediterranea? intermediate is RNA
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The nuclei will produce
mRNA and is transported to the top
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mRNA is stored as the cytoplasmic membrane and is
the source of imprint

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