Why does dna replication occur before mitosis

Y’all i need answers plss people are saying me and my brother look alike although we’re two different ages. one year apart i’m a girl, btw i’m thinking we could be fraternal twins idk my parents and my friends think we look alike

Casts and mold are a type of preservation where the original material decays, leaving a mold in surrounding rock that can be filled with another sediment a. true b. false

Has anyone taken the genetics unit test in connexus? not looking for answers, just a little bit what to expect and some with studying.