Chapter 2

An ecosystem consists of a community of organisms in a physical environment.

Almost all terrestrial ecosystems depend on the ability of plants to capture energy from the ______ and store it in complex organic molecules.

In ecosystems with enclosed canopies, the most intense competition among plants is likely to be for ___________.

Competition occurs when plants of the same or different species attempt to use a resource that is in limited supply.

If new species attempt to colonize an ecosystem but lack open niches or unexploited resources, the result is known as ____________.

Plants that colonize niches in crop ecosystems are known as ____________.

Parasites differ from herbivores because they cause ____________ rather than simply eating their way through plant tissues.

Which of the following is an example of a biocontrol administered into a field of sweet corn?

Mycorrhizae and Lichens are examples of symbionts.

What is added to crop ecosystems that relegate saprophytes and detritivores unnecessary?

When explorer Alexander von Humboldt moved north or south from the equator or ascended in altitude in different parts of the world, he noticed that there was a similar progression of vegetative types and climatic conditions. Today, we call the recurrent vegetation and climatic condition types ______.

Natural ecosystems are known to be highly conservative regarding nutrients.

In the food web of a natural ecosystem, plants are known as _____________.

______________ is the main influence on the type of vegetation that develops.

Soils are produced from parent material by the interaction of climate and bacteria.

______________ availability is primarily affected by patterns of air circulation around the globe.

In general, surface winds from latitudes 30o N and 30oS travel away from the equator.

At the ______________, temperatures are high throughout the year.

The roots of ____________ never reach bare mineral soil.

The tropical rainforests of South America, Africa, India and southern Florida make up the most productive biome and largest range of biological diversity on earth.

Low temperature can be overcome more easily than lack of water for crop production.

Net primary productivity or NPP is ____________ fixed minus the amount consumed by the plant.

All locations in a geographic area tend to develop __________________ kinds of vegetation over time.

The THEORETICAL end point of ecological succession is known as the _______________________.