Amineral that has can be split fairly easily along planes with weak atomic attraction.

Answer : spaced planes of weakness

I am not 100% sure but This is what I remember

I hope that's help :)

did you fail the test? xd

during the process of dna replication, brdu can replace thymidine and incorporate into the newly synthesized dna, cell proliferation thus can be reflected in the extent of brdu incorporation.