1. < BackNext >PreviewMain Section 2 Marine Ecosystems Chapter 20 Life in the Ocean Abiotic Factors Marine ecosystems are shaped by abiotic factors including _________________, _______________, and the ________________ that passes into the water. Plankton Trillions of plankton live in the ocean. Plankton are ____________________________ _______________________________________.

2. < BackNext >PreviewMain Section 2 Marine Ecosystems Chapter 20 Temperature Depth and Temperature The temperature of ocean water ______________ as the depth of the water increases.

3. < BackNext >PreviewMain Section 2 Marine Ecosystems Chapter 20 Depth and Sunlight The Intertidal Zone The intertidal zone is the place where ____________________________. The Neritic Zone As you move farther away from shore, into the neritic zone, the water becomes ______________________. The Oceanic Zone In the oceanic zone, the sea floor _____________________________ The Benthic Zone The benthic zone is the ocean floor. The deepest part does not get any ________________________.

4. < BackNext >PreviewMain Section 2 Marine Ecosystems Chapter 20

5. < BackNext >PreviewMain Section 2 Marine Ecosystems Chapter 20

6. < BackNext >PreviewMain Section 2 Marine Ecosystems Chapter 20 A Closer Look Intertidal Areas Intertidal areas are found _____ the shore. These areas include mudflats, sandy beaches, and rocky shores. Coral Reefs Coral reefs are found in ________, ___________ areas of the ________zone. Reefs provide homes for many marine animals and plants. Estuaries An area where _______________ from rivers spills into the ocean is called an estuary. Plants and animals living in estuaries must be able to survive in a changing concentration of salt.

7. < BackNext >PreviewMain Section 2 Marine Ecosystems Chapter 20 A Closer Look, continued The Sargasso Sea An ecosystem called the Sargasso Sea is found in the middle of the _____________ Ocean. The ecosystem contains floating rafts of __________. Polar Ice The Arctic Ocean and the ocean around Antarctica have icy waters, which are rich in _________________. Many fishes, birds, and mammals live in this ecosystem.

8. < BackNext >PreviewMain Section 3 Freshwater Ecosystems Chapter 20 Stream and River Ecosystems Water in Streams and Rivers The water in brooks, streams, and rivers may flow from melting ice or snow. Or the water may come from a spring. Tributaries Each stream of water that joins a ________________________is called a tributary.

9. < BackNext >PreviewMain Section 3 Freshwater Ecosystems Chapter 20 Pond and Lake Ecosystems Life near Shore The are of water ____________ to the edge of a lake or pond is called the littoral zone. The plants in the littoral zone are homes to small animals. Life Away from Shore The area of a lake or pond that extends from the littoral zone ____________ of the water called the open-water zone. Beneath the open-water zone is the deep-water zone, where _________________ reaches.

10. < BackNext >PreviewMain Section 3 Freshwater Ecosystems Chapter 20

11. < BackNext >PreviewMain Section 3 Freshwater Ecosystems Chapter 20 Wetland Ecosystems Marshes A _________ wetland ecosystem where plants, such as grasses, grow is called a marsh. Muskrats, turtles, frogs, and birds live in marshes. Swamps A wetland ecosystem in which _______ ______________ grow is called a swamp. Water lilies and other plants grow in standing water. Many fishes, snakes, and birds also live in swamps.

12. < BackNext >PreviewMain Section 3 Freshwater Ecosystems Chapter 20 From a Lake to a Forest Build Up of Sediments Water entering a standing body of water usually carries _________ and __________________. These materials build up on the bottom of the lake or pond. Formation of a Wetland Over time, the pond or lake is filled with sediments. Plants grow in the new soil and the pond or lake starts becoming a ___________________. The wetland then may develop into a _____________.