What is biodiversity?
Biodiversity is a combination of two words, Bio (life) and diversity (variety). In simple terms, it is the number and variety of organisms found within a specified geographic region. It refers to the varieties of plants, animals and micro-organisms, the genes they contain and the ecosystems they form.
It relates to the variability among living organisms on the earth, including the variability within and between the species and that within and between the ecosystems. Biodiversity is our living wealth and a result of hundreds of millions of years of evolutionary history. It can be discussed at three levels: Genetic diversity, Species diversity, and Ecosystem diversity.
Explanation
The answer defines biodiversity using the exact phrasing from the NCERT textbook context. It starts with the etymology of the word, provides the simple definition regarding the variety of organisms in a region, and expands to include genes and ecosystems. It also mentions the three levels of biodiversity (Genetic, Species, and Ecosystem) as outlined in the text to ensure a comprehensive 2-mark answer.