Which of these is a type of mutation where a single base pair in the dna is exchanged for another?
insertion
deletion
substitution
creation

How can a geological time scale best be reconstructed? a) comparing vestigial structures in living species b) comparing homologous structures in living species c) examining homologous structures in fossil remains d) examining the written records of scientists from past cultures

When new rock is added to an oceanic ridge, the magnetized strips on either side of the ridge are evidence of sea-floor spreading. this is because the rocks on the two sides of the ridge o are equal in width and in polarity are polar opposites oare magnetized vary in width but are equal in polarity

Genetic disorders can result when sister chromatids fail to seperate properly. during what phase is this problem most likely to occur?