What are the Different Types of Algae, and How Do They Impact Our Lives?

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What are the Different Types of Algae, and How Do
They Impact Our Lives?

• The Two Most Dominant Forms of Microalgae
  (Kingdom Protista)
• Division Bacillariophyta (Diatoms) pennate and
  centric forms shells made of silicon dioxide
  (glass) often form chains (incr. surface area
  slows sinking)
• Division Dinophyta (Dinoflagellates) spines and
  toxins for defense (ex., domoic acid can cause
  paralytic/amnesiac shellfish poisoning) include
  bioluminescent and symbiotic forms plates of
  cellulose
• Classification of Macroalgae (Seaweeds, Kingdom
  Protista)
• Division Chlorophyta (Green Algae) with
  chlorophyll ex. sea lettuce (Ulva)
• Division Rhodophyta (Red Algae) with
  phycocyanin examples Nori, foliose and
  calcareous forms (coralline algae, include
  encrusting forms)
• Division Phaeophyta (Brown Algae) with
  fucoxanthin include turf forms and larger kelps
  (with stipes, blades, and holdfasts)
• Ecological Importance of Algae primary
  producers, provide habitats (ex. kelp forests)
  some compete with corals
• Photosynthesis 6CO2 12H2O ? C6H12O6 (glucose)
  6O2 6H2O
• Practical Uses of Algae kelps harvested for
  algin and carrageenan (solidifying agents, food
  additives) kelps once a source of potash (for
  explosives)

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Figure 5-23
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Typical Algae in Southern California Tide Pools

• Coralline algae
• Rockweed ?

• Dead Mans
• Fingers
• (Codium)
• Sargassum ?

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Figures 4-4a and 4-6b
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Figure 4-19
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What are the Different Types of Marine Plants?

• Division Anthophyta with seeds and flowers
  marine forms are halophytes (salt-tolerant)
• Submergent Plants remain submerged
• Seagrasses include eel and turtle grasses food
  for manatees, dugongs, sea turtles sheltered
  areas
• Emergent Plants coastal and intertidal forms
• Surfgrasses found in rocky intertidal zones
• Mangroves found in tropics in areas of low wave
  action seeds float some with pneumatophores
  important habitat for juvenile fishes reduce
  sedimentation offshore
• Marsh Plants include pickleweed, cord grass,
  salt grass absorb nutrients (some cities use
  for sewage treatment)

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Surfgrass
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Figure 5-26
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Marsh Plants (Pickleweed and Salt Grass)