Do Now• What are the three types of algae?

• What is the corriolis effect?

• What is Ekman transport?

Objective • Objective: Students will learn the three types of algae and the

parts of seaweeds through a bingo game. SWBAT understand the different life histories used by seaweeds

Multicellular Primary ProducersSeaweeds and PlantsChapter 6

All photosynthetic?

Most are photosynthetic but of course there are exceptions

Some are not photosynthetic and are actually parasites of other seaweeds!

The role of seaweeds• Transform solar energy to chemical energy in the form of

organic matter• Energy is then available for consumption

• Habitat• Oxygen producers

Structure of seaweeds• Seaweeds are eukaryotic

• Seaweeds still lack the specialized structures and reproductive mechanisms characteristic of terrestrial plants

• Wide range of variation among seaweeds

Variation• Rocky shore- small and sturdy to withstand waves• Some delicate ones live on other seaweeds

• Kelps- found offshore in cold waters (giants)

General Structure • Seaweeds lack true leaves, stems, and roots of plants.

• Thallus- Complete body• Blades- Leaf-like flattened portions of the thallus, large surface

area, photosynthesis• Pneumatocysts- Gas-filled bladders that can keep blades close

to sea surface• Stipe- Stem-like structure for support, blades originate • Holdfast- Attaches the thallus to the bottom and well

developed in kelps

Structure

Types of Seaweeds • Three types• 1) Green• 2) Brown• 3) Red

Green Algae• Most are freshwater and terrestrial• 10% of the 7,000 species are marine• Most have a simple thallus compared to the other 2 groups• Thought that land plants evolved from green algae• Pigments and food reserve are the same

Where do green algae live? • Common on rocks in shallow water • Rocky shore tide pools

Types of green seaweeds• Filamentous types may be branched or unbranched • Enteromorpha- thin thallus in the form of a hollow tube• Ulva- Sea lettuce is paper thin• Valonia- forms large spheres or curious spherical clusters.• Caulerpa- Single giant cell with many nuclei• Codium- Deadman’s fingers• Halimeda- Calcareous green algae (coral reefs)

Enteromorpha

Ulva

Valonia

Caulerpa

Codium

Halimeda

Brown Algae• Coloration – varies from olive green to dark brown• Fucoxanthin over chlorophyll

• Almost all of the 1500 species are marine• Often the dominant primary producers on temperate and

polar rocky coasts.• Largest and structurally most complex (Include the kelps)

Types of Brown Algae • Ectocarpus- Finely filamentous thallus • Dictyota – thallus is flat and branched• Padina- Fan-shaped and lightly calcified• Desmaretia- branched

• Some are exposed at low tides at the middle and upper levels of rocky shores

• Gas-filled floats – rockweeds or wracks

Sargassum• Brown algae found in warm waters (Gulfs of Mexico and

California) • Sargasso weed has spherical air bladders to keep small leaf like

blades afloat• Most grow on rocks• Offshore in huge masses• Sargasso Sea• Area in Atlantic

Sargasso Sea

Sargassum Sea• http://www.youtube.com/watch?v=JFxhlyJ3U4Q

Kelps• Most complex and largest of all brown algae• Great importance – provide food and shelter for many

organisms. • Laminaria- species of kelp where a single large blade can be

up to 10 ft• Agarum and Alaria – Rib runs along the middle of a single

blade• Egregia- Feather boa kelp• Eisenia- Southern sea palm• Nereocystis- Bull kelp• Pelagophycus- Antler like branches

Brown Algaes• kelp.gifkelp.gif

Ectocarpus

Dictyota

Padina

Desmarestia

Laninaria

Agarum

Alaria

Egregia

Nereocystis

PelagophycusEisnia

Macrocystis• Largest of kelps• Massive holdfast attaches to the bottom• At the base of each blade a gas-filled pneumatocyst• Can grow 20 in per day in optimal conditions• Form kelp beds or forests• Among the richest, most productive environments in the marine

world

Kelp Forest• http://www.youtube.com/watch?v=GcbU4bfkDA4• What coast of North America can they be found?• What do kelps consist of?• What do young kelp compete for?• What do fish use the kelp forest for?• Why does the canopy make a good nursery environment?

Red Algae• More red algae that green and brown combined• Red pigments known as phycobilins• Essentially marine• Of the 4000 species, only a few are fresh water or soil

• Live in most shallow-water marine environments

Structure of Reds• Simplified in structure by becoming parasites of other

seaweeds• A few have lost all chlorophyll and are heterotophs• Most are filamentous • Thickness, width, arrangement of filaments varies

Types of Reds• Gelidium • Gracilaria• Endocladia – wirey clumps on rocky shores from Alaska to S.

Ca.• Gigartina- Most massive of the red algae• Porphyra-Common on rocky shores above the lowest tide

mark• Rhodymenia –Common in North Atlantic• Chondrus –Irish moss and can tolerate wide ranges in temp,

light and salinity

Red Algae• en

Gelidium Gracilaria

Endocladia

Gigartina

Porphyra

Rhodymenia

Chondrus

Coralline Algae (Corallina)• Red algae that deposit calcium carbonate in their cell walls• Important in several marine environments • Calcified thallus takes a variety of shapes• Color varies from light to intense reddish-pink• Warm-water coralline algae are actively involved in formation

and development of coral reefs

Bingo• Thallus• Blades• Pneumatocysts• Stipe• Holdfast • Green algae• Red algae• Brown algae• Enteromorpha• Ulva• Valonia• Caulerpa• Halimeda• Gigartina• Chondrus

• Fucoxanthin• Ectocarpus• Dictyota• Padina• Desmarestia• Rockweeds• Sargasso Sea• Laminaria• Nereocystis• Pelagophycus• Macrocystis• Kelp forest• Phycobilins• Coralline algae• Gracilaria• Porphyra

Exit Ticket• 1) What type of algea

is Ulva?• 2) What is the

sargassum sea• 3) What is a

pneumatocyst?