1 .		A __________ is formed by interactions among populations of living flora and fauna, and is a subdivision of an ecosystem.
2 .		The difference between photosynthetic production and respiration loss in plants is called __________.
3 .		Legumes are essential components of the __________.
4 .		The lack of water in desert climates or the low temperatures at high elevations are called __________ because they inhibit plant growth.
5 .		The __________ is the initial community that occupies an area of early succession.
6 .		Organisms that are capable of using carbon dioxide as their sole source of carbon are called __________.
7 .		The consumption of grain-fed beef in developed countries has led to inefficient __________ throughout the world.
8 .		The __________ biome is associated with Aridisols, sagebrush, and scrub vegetation, and is located in western North America.
9 .		The __________ biome is characterized by lush tree growth, including the presence of the Earth's tallest trees, and generally cool temperatures.
10 .		The __________ is the biome most modified by human activities. Naturally occurring trees there are primarily broadleaf deciduous, and occur mostly along streams.
11 .		The __________ biome is associated with low potential evapotranspiraton, D climates, and Spodosols.
12 .		Large grazing animals graze among thorn trees in the __________ biome.
13 .		This photograph shows __________.
14 .		This photograph shows the __________ biome.
15 .		This photograph shows the __________ biome.
16 .		The biome in this photograph is __________.
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