The Wonderful World of Plankton

What do we already know about Plankton?

• Autotrophic • Primary producers • Important to life on earth

– Produce oxygen – Consume carbon dioxide out of the

atmosphere

• Drifters • Phytoplankton and zooplankton

Three types of plankton we will be studying

• Diatoms

• Dinoflagellates • Formaminiferans

• ALL ARE EUKARYOTIC, SINGLE CELLED ORGANISMS

Dia

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Diatoms

• Single Celled organisms

• Phytoplankton – Account for 25% of

all phytoplankton on earth

Diatoms: Structure

• Characterized by their frustule: a two part organic box that encloses the diatom – Made up of two valves:

one larger than the other.

• Surface of frustule: porous, groves, spines, hooks

• Geometric patterns – Looks: like glass, fragile

• Made of silicon

Diatoms: Structure

• Radial symmetry: circular symmetry

• Bilateral symmetry: parallel symmetry

Diatoms: Reproduction • Fission

– Splitting in half

• Cell divides: each daughter cell inherits one side of the frustule (a valve) – Grows a new smaller valve inside

frustule

• 50% of each generation is smaller than the last

• too small forms an auxospore: increases volume back to original size

• In summer seasons more than 1 million diatoms can come from a single parent

Diatomaceous Earth

• Used to Filter – Beer– Pools – Champagne

• Abrasive used in – Toothpaste – Silver polish

• Soundproofing • Insulation

Economic Value

• diatoms’ glass like frustule does not dissolve in water – Settles to the bottom

of the sea– Pressure

• Fossil Fuels

Can cause Health Risks

• Diatoms Cause harmful toxic blooms • Some produce toxins• How would this be dangerous to humans?

Diatoms: CFU

• How do diatoms consume energy?• What are two economical impacts of

diatoms? • What are two environmental impacts of

diatoms? • How do diatoms reproduce • What are diatom’s characteristic structure

Din

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Dinoflagellates

• Gobular, Single celled organisms

• Some– platonic – others are benthic

• Some – symbiotic – others parasitic

Dinoflagellate: Structure

• Two groves: two flagellums – Horizontal: cingulum

• Spinning flagellum

– Vertical: suclus• Whipping flagellum:

forward motion

Dinoflagellates: Structure

• Outer structure is made up of plates

• Armored Dinos: – Spines, other

structures – Help with predation,

floatation

Dinoflagellates: food/digestion

• Many are mixotrophic • They have Chloroplasts:

– Photosynthesis

• But also absorb food – Osmotrophy – Eat other plankton:

copepods, diatoms, other dinoflagellates

Dinoflagellates: reproduction

• Binary Fission: one division per day

• Can depend on conditions: – nutrients, light,

temperature

Dinoflagellates: ecological Role

• Red Tides– Release toxins– Digestion of toxins

can cause: numbness, slurred speech, nausea, paralysis, death

– Paralytic shellfish poisoning

For

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Foraminiferans

• Amoeboid protozoans – Branch like

psuedopods – Form elaborate net

like structures: Tests • Help catch prey

• Most are benthic – Use psuedopod to

crawl around

Forams: digestion/energy

• Consume a lot of diatoms and dinoflagellates

• Some host green/red algae – Symbiotic

relationship • Forams get nutrients • Coral reefs get

calcium carbonate

Forams: Structure

• Produce Elaborate Tests– Multichamber– Grow as the foram

grows

• Geometric– Resembles

microscopic snail shell

Forams’ ecological role

• Hel form beaches and sediment – Chalk