<span>A protonephridia is known as a flame cell because it is a specialized excretory cell. This simply means that these cells have the ability to remove waste materials within an organ of a particular living organisms. Some freshwater invertebrates, flatworms, and rotifers have these specialized cells within their systems.<span>
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Allele frequencies in a population may change due to four fundamental forces of evolution: Natural Selection, Genetic Drift, Mutations and Gene Flow. Mutations are the ultimate source of new alleles in a gene pool. Two of the most relevant mechanisms of evolutionary change are: Natural Selection and Genetic Drift.
That era would be the <span>Pleistocene Epoch.</span>
Answer:
True, they work side by side
Explanation:
