What is the correct term for a large number of species in an ecosystem?

The correct answer is biodiversity.

Explanation:

A large number of species in an ecosystem can be collectively termed as biodiversity. Biodiversity is the most composite characteristic of the planet and plays an essential part. Biodiversity comprises different levels, beginning with the genes, then individual species, then communities, and eventually the whole ecosystems like coral reefs or forests. These innumerable associations have made Earth suitable for living.

i would say the prokaryotic cells the prokaryotic cells are less complex, are usually found only in unicellular organisms and have more limited capabilities than eukaryotic cells.