Answer:
The species richness of a community refers to the number of different species. B)
Answer:
A dam that could allow fish to still pass through is a fishway/fish pass its a "fish ladder" that is structured on or around artificial or natural barriers to allow for fishes natural migration and the movement for potamodromous species.
A species is an integrated group of populations, integrated through their form, behavior, and preferred living conditions, the consequence of similar DNA and reproductive isolation from other species. A population is several organisms of the same kind in a particular area.
In unicellular organisms, the process of mitosis serves as a method or form of asexual reproduction, as organisms that are unicellular and are typically prokaryotic undergo mitosis to essentially duplicate and make additional offspring that are genetically identical clones as that of the original parent cell. Mitosis in multicellular organisms serves to replace lost, specifically damaged tissue of the organism, it also is crucial for the growth and development of the organism, as it is this particular portion of the cell cycle, when cells after growing and having their DNA duplicated can they separate and produce more and more cells.