Freshwater Ecosystems

Eutrophic lakes are characterized by...

• low nutrients, low oxygen
• low nutrients, high oxygen
• high nutrients, low oxygen
• high nutrients, high oxygen

Where would you find cattails and reeds?

• Limnetic zone (aphotic)

• Littoral zone

• Limentic zone (photic)

• Benthic zone

Plankton are NOT....

• top carnivores of pond food webs
• tiny, microscopic organisms
• easy prey for other aquatic life
• producers

______ are all organisms that swim freely, independent of currents.

• Benthos

• Zooplankton

• Nekton

• Phytoplankton

Organisms that live on the bottom of aquatic ecosystems are known as

• plankton

• benthos

• nekton

• predators

Which is NOT a freshwater ecosystem?

• a river
• a lake 
• an estuary
• a stream

Headwaters are

• the end of a river.

• also know as wetlands.

• the start of a river.

• small ponds.

What aquatic biome is characterized by flowing fresh water?

• Lakes/Ponds

• Wetlands

• Rivers/Streams

• Coral Reefs

_____________ are wetlands that are dominated by woody plants, such as trees.

• marshes

• swamps

• estuaries

• mangroves

The plankton that are microscopic and plant like are called

• zooplankton

• phytoplankton