Ecologist use similarities between ecosystems to classify them into broad categories called

• biomes.
• littoral zones.
• estuaries.
• benthic zones.

Over a given unit of time, the rate at which plants and algae convert solar or chemical energy into energy stored in the bonds of organic sugars is called

• natural selection.
• gross primary production.
• salinity.
• estivation.

WEATHER describes the average conditions, including temperature and precipitation, over long periods in a give area.

• True
• False

WARM AND WET biomes have the lowest net primary production.

• True
• False

Which biome would have the lowest net primary production?

• tropical rain forest
• temperate grassland
• coral reef
• desert

Why do short trees and plants that make up the understory in tropical rain forests have large, flat leaves?

• to shade themselves from excessive sunlight
• to create habitat for forest insects
• to offer protection from rain
• to allow maximum surface for light absorption

In the temperate rain forests, trees such as cedars and spruces, which do not lose their leaves at anytime of year, are called

• coniferous.
• succulent.
• chaparral.
• deciduous.

To help them survive in the tundra, caribou have various adaptations, such as

• thin coats of fur to prevent overheating.
• wide hooves for travel on mud and snow.
• a diet that consists mostly of deciduous tree leaves.
• the ability to hibernate.

Most trees in tropical dry forest are

• deciduous
• intertidal
• photic
• coniferous
• limnetic

Criteria such as salinity, depth, and whether the water is flowing or standing are used by scientists to

• classify aquatic ecosystems.
• measure net primary productivity in lakes.
• distinguish aquatic ecosystems from terrestrial ecosystems.
• determine the number of species in a body of water.