| A | B |
|---|
| How much of Earth's surface is covered with water. | 3/4 |
| What are five factors determine the conditions within an aquatic ecosystem? | The depth, flow, temperature, chemistry of the water above it, and latitude. |
| How much of Earth's surface is covered with fresh water? | only 3% |
| Into which two categories are freshwater ecosystems divided? | 1) flowing-water ecosystems; 2) standing-water ecosystems |
| Name some adaptations that organisms have made to enable them to live in a flowing-water ecosystem. | Some larvae: hooks allowing them to hold on to aquatic plants; some catfish: suckers that anchor them to rocks; trout: streamlined bodies help them move with or against the current. |
| What are the most common standing-water ecosystems? | lakes and ponds |
| Why is water circulation important in a standing-water ecosystem? | It distributes heat, oxygen, and nutrients throughout the ecosystem. |
| What is plankton? | They're tiny, free-floating, weakly swimming organisms that occur in aquatic environments. |
| What are phytoplankton? | It's the population of single-celled algae and other small, photosynthetic organisms found near the surface of the ocean and forming part of plankton. |
| What is zooplankton? | Tiny animals that form part of the plankton. |
| What is a wetland and what are the three main types? | An ecosystem in which water either covers the soil or is present at or near the surface of the soil for at least part of the year; bogs, marshes, and swamps are the most common types. |
| Describe a bog. | Wetland; dominated by sphagnum moss; in depressions where water collects; water often acidic. |
| Describe a marsh. | Shallow wetland; along rivers; underwater all or part of year; have cattails, rushes, tall, grasslike plants. |
| What differentiates a swamp from a marsh? | Trees and shrubs grow in a swamp; tall, grasslike plants grow in marshes. |
| Why do plankton grow well in lakes and ponds? | Plankton would be washed away by flowing water, so quieter waters in lakes and ponds allow it to grow. |
| What is an estuary? | a wetland formed where rivers meet the ocean (i.e., where the Mississippi R. meets the ocean) |
| What is detritus? | Particles of organic material that provide food for organisms at the base of an estuary's food web. |
| Describe a salt marsh. | temperate-zone estuary dominated by salt-tolerant grasses above the low-tide line and by seagrasses under water; one of largest in US=around Chesapeake Bay estuary in Maryland. |
| Describe a mangrove swamp. | coastal wetland dominated by mangroves, salt-tolerant woody plants; in tropical regions; valuable nurseries for fish & shellfish; largest US one=Florida's Everglades |
| What is a photic zone? | the well-lit upper layer ofthe oceans; photosynthesis is limited to this zone; goes to about 200m deep. |
| What is an aphotic zone? | the permanently dark layer of the oceans below the photic zone; chemosynthetic autotrophs are the only producers found there.(see diagram, pg. 109) |
| What are the zones specified by marine biologists? | photic; apotic; intertidal; coastal; open ocean. |
| What is the benthic zone? | It covers the ocean floor. |
| What types of changes must intertidal organisms endure? | Once or twice/day, they're submerged in sea water--sometimes with waves & strong currents; other times, air, sunlight, and temperature changes affect them. |
| What is zonation? | the prominent horizontal banding of organisms that live in a particular habitat (see pg. 110) |
| Where is the coastal ocean? | It goes from the low-tide mark to the outer edge of the continental shelf (the shallow border surrounding the continents); most of it is within the photic zone. |
| Describe a kelp forest. | Coastal ocean community; kelp growing (giant brown alga) rapidly; support food web including snails, sea urchins; sea otters; fishes; seals; whales. |
| What is a coral reef? | It's a diverse and productive environment named for the coral animals that make up its primary structure (hard, calcium carbonate skeletons); see pg. 111. |
| What organism lives in a symbiotic relationship with coral? | algae; algae carry out photosynthesis using the coral animals' wastes as nutrients; algae give coral certain essential carbon compounds. |
| Describe the open ocean. | begins at edge of continental shelf; largest marine zone; covers more than 90% of world's oceans; goes from 500m deep to more than 11,000m.;low levels of nutrients; support only smallest producers; all types/sizes of fishes there. |
| What is the benthos? | They're organisms living attached to or near the ocean floor; examples of organisms there: clams, sea cucumbers. |
| What has damaged some coral reefs in the Pacific Ocean? | Crown-of-thorn starfish prey on corals, and they have attacked coral in the Pacific. |
| Where in the U.S. are coral reefs found? | Only the coasts of southern Florida and Hawaii have coral reefs. |
| On what standard are the main divisions in the ocean based? | They're based on depth and distance from shore. |
| What ocean conditions support the existence of mangrove swamps and salt marshes? | Areas were large ocean waves are not found, as large waves would not allow the grasses and trees to stay rooted. |
| What are the 4 chief factors that affect aquatic ecosystems? | depth, flow, temperature, chemistry of the overlying water |
| Name the abiotic factors that characterize salt marshes. | temperate zone climate, saltwater, tides |
