Explanation:

Definitions of 2 and 3 are interchanged Biome

• a large community unit, characterized by a major vegetation type and associated fauna, found in a specific climatic region

• No two biomes are alike Ecotone

• Transitional area between two biomes or diverse ecosystems (where two communities meet & integrate)

• Examples : between a field and forest, between forest and grassland

• may appear as a gradual blending of the two communities across a broad area, or may manifest itself as a sharp boundary line

• May contains some organisms which are entirely different from that of adjoining communities

• Sometimes the number of species & population density of some of the species is much greater in this zone than either community, Known as edge effect

• Organisms which occur primarily or most abundantly in this zone are known as edge species Niche

• Description of all the biological, physical & chemical factors that a species needs – to survive, stay healthy & reproduce

• Niche is unique for every species which means no 2 species can have exact identical niche