Temperature and moisture are key factors in determining where each of the seven occur.

The given blank can be filled with biomes.  

Biomes are illustrated as the world's major communities, categorized on the basis of the predominant vegetation and featured by amendments made by the species to thrive in that specific environment.  

The seven biomes of the world are tundra, taiga, temperate deciduous forest, scrub forest, desert, grassland, temperate rainforest, and tropical rainforest.  

The two most important elements that determine the biome of an area are majorly the temperature and precipitation. It is because, these two factors restrict the species of plants, which can grow in a region.  

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