Classification of Marine Life & Habitats
OCN 201 Biology Lecture 3 Grieg Steward Autotrophs can make the organic building blocks of Heterotrophs have to eat organics life starting from carbon dioxde
nucleotides
sugars
C H S H amino acids H lipids Classifying Marine Organisms by Nutrition
Autotrophs - use CO to make organics • 2 • Who: All plants, some protista and bacteria • Can use sunlight (photo-) or chemical (chemo-) energy • Heterotrophs - Need to consume organic compounds • Who: everything that is not autotrophic • Mixotrophs - They can do both! Autotrophy (photosynthesis or chemosynthesis)
Energy Autotrophic Cell
6CO2 + 6H2O C6H12O6 + 6O2
Sugar
Cells are more than sugar. Other compounds are built from simple sugars plus nutrients (Nitrogen, Phosphorous) & trace metals) Respiration Reversing the reaction yields energy the cell can use
Autotrophic Cell
6CO2 + 6H2O C6H12O6 + 6O2
Energy Respiration Heterotrophs consume organics. Much is respired to get energy and some is used as building blocks to grow.
Heterotroph
6CO2 + 6H2O C6H12O6 + 6O2
Energy Animals Heterotrophs Fungus Heterotrophs Macroalgae & Plants Photoautotrophs Photoautotrophs Protists Heterotrophs Mixotrophs
Photoautotrophs Chemoautotrophs Bacteria and Archaea Heterotrophs Mixotrophs
3.8 bya 2 bya Today 7 Classifying Marine Organisms by Habitat • Benthic (benthos = bottom) • Pelagic (pelagius = of the sea)
Ocean Habitats
Intertidal PELAGIC (littoral) BENTHIC zone Classifying Marine Organisms by Lifestyle
Epifauna • Benthic (benthos = bottom) • Infauna Epifauna • Infauna • Pelagic (pelagius = of the sea) • Plankton (Drifters, weak swimmers) • Nekton (Swimmers) Pelagic Organisms 35 mm
Nekton (all are animals)
5 mm Plankton phytoplankton zooplankton bacterioplankton Physical Divisions of the Marine Environment
Supralittoral (splash zone) NERITIC OCEANIC
Epipelagic 200 m Sublittoral Littoral Mesopelagic (intertidal) 1000 m
Bathypelagic Bathyal
4000 m
Abyssal Abyssopelagic 6000 m Hadalpelagic Hadal Physical & Chemical Factors Affecting Life
• Temperature & Light DECREASE with Depth & Latitude • Pressure INCREASES with Depth • Salinity more variable near shore • Air exposure in the littoral zone Pressure Increases with Depth
Photo courtesy Kate Achilles Deep-diving marine mammals have collapsible lungs Temperature Variations
Temperature Decreases with Depth
Temperature Decreases with Latitude
POLAR TEMPERATE
TROPICAL TEMPERATE
POLAR TOTAL light and COLOR Spectrum Vary with depth
Red Yellow Green Blue UV Euphotic zone= where photosynthesis is possible! “Good” Light Euphotic 20 to 100 m
Twilight Disphotic Disphotic zone= there is light but not enough for photosynthesis! about 600 m No Light Aphotic No light from the sun penetrates Photosynthesis Feeds The Ocean
Energy
Food The Pelagic Divisions (By Light)
Photosynthesis can only EUPHOTIC ZONE “Good” Light happen up here! 20 to 100 m
DISPHOTIC ZONE Twilight
about 600 m APHOTIC ZONE No Light
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