1. Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
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2. Where the Ocean Meets the Land
Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
Where the Ocean Meets the Land
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3. Where the Ocean Meets the Land
Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
Where the Ocean Meets the Land
The Intertidal Zone
The intertidal zone is the area between the high- and low-tide lines.
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4. Where the Ocean Meets the Land
Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
Where the Ocean Meets the Land
The Intertidal Zone
At high tide, the area is completely under water, while at low tide, the area is exposed to air.
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5. Intertidal habitats depend on land features at the shore.
Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The Intertidal Zone
Intertidal habitats depend on land features at the shore.
For instance, low parts of rocky cliffs might have plants that can survive out of water during low tide.
Sandy beaches hide crabs and clams that burrow under sand to await the rising tide.
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6. Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The Intertidal Zone
Tide pools may contain crabs, small shrimp, sea anemones, sea stars, sea cucumbers, snails, and a variety of small plants.
These organisms are sheltered from large fish at high tide because of crashing waves, but are in danger of being eaten by birds at low tide.
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7. The Intertidal Zone Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
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8. The Intertidal Zone Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
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9. The Intertidal Zone Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
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10. The Richness of the Reef
Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The Richness of the Reef
The Near-Shore Zone
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11. The Richness of the Reef
Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The Richness of the Reef
The Near-Shore Zone
The near-shore zone is home to many species of fish, jellyfish, and seaweed & corals.
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12. The Richness of the Reef
Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The Richness of the Reef
The Near-Shore Zone
Coral individuals, called polyps, live in colonies.
Polyps produce hard exoskeletons attached to those of their neighbors.
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13. Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The Near-Shore Zone
Coral reefs are the branch-like structures built by colonies of coral polyps.
The branched reefs provide habitats for many organisms, which form a complex community and food web.
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14. The Near-Shore Zone Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
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15. The Near-Shore Zone Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
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16. The Wide and the Deep The Open-Ocean Zone
Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The Wide and the Deep
The Open-Ocean Zone
Animals at the surface in the open ocean are much like those living near shore.
Fish, sea turtles, and whales move between near-shore and open ocean zones.
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17. Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The Open-Ocean Zone
As you move deeper in the ocean, light decreases, pressure increases, and temperature drops.
Organisms, such as squid, that live in those extreme conditions are very different from those that live near the surface.
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18. The Open-Ocean Zone Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
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19. Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The Open-Ocean Zone
Communities of shrimp, crabs, tubeworms, slugs, and even fish form around hydrothermal vents, volcanic spots on the ocean floor.
Bacteria there eat dissolved chemicals in the heated water.
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20. The Open-Ocean Zone Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
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21. The bacteria start the food chain for larger organisms.
Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The bacteria start the food chain for larger organisms.
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22. Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
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23. The Most Important Organism You Never See
Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The Most Important Organism You Never See
Plankton are microscopic, drifting organisms that inhabit the wide open ocean.
Plankton reproduce in such massive numbers that they form clouds in the water visible from space.
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24. The Most Important Organism You Never See
Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The Most Important Organism You Never See
Plankton aren’t a single species. They are a group that includes plantlike organisms, animal-like organisms, and bacteria.
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25. The Most Important Organism You Never See
Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The Most Important Organism You Never See
Plantlike plankton make their food through photosynthesis, which releases oxygen back into the atmosphere, enabling us to breathe.
Animal-like plankton feed on other plankton.
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26. The Most Important Organism You Never See
Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The Most Important Organism You Never See
Large and small animals filter plankton from the water as their food. Smaller fish, in turn, become food for bigger predators.
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27. The Most Important Organism You Never See
Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The Most Important Organism You Never See
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28. The Most Important Organism You Never See
Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
The Most Important Organism You Never See
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29. Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
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30. Unit 11 Lesson 4 What Are Some Ocean Ecosystems?
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