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What does gradualism and punctuated equilibrium have in common

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

Which statement best describes the relationship between an allele and a gene? question 1 options: an allele is a variation of a gene that can be expressed as a phenotype. an allele is the part of a gene that attaches to messenger rna molecules. an allele is a segment of a dna molecule that controls replication of a gene.