Which statement correctly defines a biome and provides representative examples with typical climate and flora?

• A. A group of ecosystems with similar climates but different species.
• B. A large ecological community defined by climate and dominant vegetation; e.g., tropical rainforest (hot, wet) and tundra (cold, low vegetation).
• C. A system of rivers and lakes with nutrient cycling.
• D. A type of habitat defined by competition among species.

Answer: (B)

Biomes are large geographic zones defined by long-term climate patterns and the dominant vegetation that shapes the habitat there. This is why a tropical rainforest (hot and wet) and tundra (cold with low vegetation) are classic examples—they reflect the climate conditions and the vegetation types that set the stage for the plants and animals in each region. The statement that best fits this idea describes a large ecological region defined by climate and dominant vegetation, and it gives representative examples with typical climate and flora. Other options miss the defining feature of a biome: one talks about similar climates but different species without emphasizing the overarching vegetation; another describes a hydrological system of rivers and lakes; and another refers to a habitat defined by competition among species, which focuses on interactions at smaller scales rather than broad climate–vegetation patterns.