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
tom
s
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
ofla
gella
tes
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
amin
ifera
ns
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