Unit 6 and 7 Review

What factor contributes most to the sustainability of a habitat?

• Competition among large predators

• Large variety of organisms

• Presence of volcanic rock

• Absence of bacteria

Scientists studying two adjacent ecosystems observe different varieties of organisms in the two areas. All of the following factors would contribute to the differing varieties of organisms in these two habitats EXCEPT

• climate

• soil type

• water resources

• wind

The ecosystem with the greatest sustainability will be the one that has the -

• greatest variety of different organisms.

• highest annual precipitation.

• lowest population of harmful insects.

• fastest growing season for green plants.

The Brazilian rain forest is an area with significant biodiversity. As the rain forest is replaced with agricultural land, it is reasonable to predict a reduction in -

• consumption of solar energy.

• sustainability over time.

• average daily temperature.

• precipitation

The ocean ecosystem has a high sustainability because of -

• strong, persistent currents.

• predator/prey relationships.

• green plants growing on the bottom.

• the large variety of different organisms.

As species disappear from a prairie ecosystem, their disappearance results in decreased -

• sustainability of the prairie ecosystem.

• numbers of species in nearby ecosystems.

• likelihood of prairie wildfires breaking out.

• numbers of offspring in remaining species.

An example of a typical pioneer species, that is one that appears in the earliest stages of ecological succession, is -

• oak tree

• spiders

• weeds

• humans

Ecological succession takes place in an area where -

• changes in the communities species composition occurs over time.

• an invasive species is artificially introduced.

• large organisms out-compete smaller organisms.

• weeds grow in a garden next to vegetables.

Plants that have deep roots, which extend, are able to reach cooler regions and absorb water that the roots of other plants can’t reach. This adaptation is expected in a habitat with which of the following climatic conditions?

• cool and sunny

• hot and arid

• wet and cloudy

• cold and dark

Which of the following characteristics is shared by both primary and secondary consumers?

• Uses the Sun’s radiant energy to produce food

• The first step in any food chain diagram

• Eats only plants to gain needed energy

• Gains energy by eating other living things