1. Climate: This is the most significant factor. Biomes are largely defined by their climate, which includes:

* Temperature: Different biomes have distinct temperature ranges and fluctuations throughout the year. This dictates which plants and animals can survive in a given area.

* Precipitation: The amount and distribution of rainfall directly influences the types of vegetation and the overall ecosystem.

* Sunlight: The amount of sunlight a biome receives affects the rate of photosynthesis and therefore the productivity of the ecosystem.

2. Geography/Topography: The physical features of a region also play a crucial role in shaping biomes:

* Elevation: Higher elevations generally experience colder temperatures and different precipitation patterns, leading to unique plant and animal communities.

* Latitude: Biomes are often arranged in latitudinal bands, with different climate conditions resulting in distinct ecosystems.

* Proximity to water: Coastal areas experience different temperature and precipitation patterns compared to inland regions, influencing the development of specific biomes.

These two factors, climate and geography, interact in complex ways to determine the characteristics of a particular biome.