Can someone please help me

How can antibodies "remember" a particular bacterial invader or "antigen" on that invader?

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

During the process of two rails or sides break apart and attract new nucleotide bases to form a new and complete strand.