Marine Ecosystems
8th Grade Science, SWMS
Types of Organisms
• Organisms classified based on:
– How they move
– Where they live
• Three types:
– Benthos
– Plankton
– Nekton
Benthos
• Live on or near bottom of ocean
– Snails, Starfish
• Sometimes attached to ocean floor
– Kelp Forests, Sponges
Plankton
• Tiny organisms that move due to currents.
– Zooplankton- animal like. Example: Krill
– Phytoplankton- plant-like. Example-algae and
diatoms.
Nekton
• Free-swimming
• Found in all layers of ocean
• Examples: Fish, Whales, Eels, Seals, etc.
Oceanic Zones
• Three different zones based on distance from
shoreline.
– Intertidal
– Neritic
– Oceanic
• Each house different organisms!
**1**
Intertidal
• Description: Shoreline area between
high and low tide mark.
• Organisms: sea anemones, starfish,
crabs, seaweed, barnacles, birds
• Adaptations: Need to be to survive
at high tide and low tide. Be able to
hang on and not get washed away
by the waves.
• Characteristics of the water:
Shallow.
Neritic Zone
• Description: gentle slope from the shore to the
deeper ocean floor.
• Organisms: coral reefs, kelp forests, fish, algae,
starfish, eels, clownfish, sea anemones, turtles
• Adaptations: Home to most life in the oceans.
• Characteristics: Fairly constant temperature,
sunlight, and salinity. Ocean depth up to 200
feet.
Neretic Zone
Coral reef
First day
(coral reefs and kelp forests)
nemo
Oceanic Zone
• Description: Deep open waters. Hydrothermal vents
• Organisms: whales, dolphins, sharks, squid, jellyfish,
krill.
• Adaptations: Most live in top 200 meters of the
surface.
• Characteristics: Sunlight only in the top 200 meters.
High pressure and low temperatures below 200
meters. No sunlight and dark below 200 meters.
Oceanic Zone
Angler attack
Angler
nemo
Hydrothermal Vents
• Seawater moves into
ocean from cracks in
Earth’s crust.
• High temperatures
• Chemosynthesisbacteria use chemicals
to make oxygen.
• Unique ocean life!
Challenger Descent
• Images
• Full length