When you visit a DDS Customer Service Center, you'll need: 1  your birth certificate, your current US passport or other proof of citizenship. 2  your Social Security Card or other verification of your Social Security Number.  two proofs of residence (recent utility bills, bank statements and rental contracts all work)
Crossing over begins early in prophase I of meiosis. At the time, homologous chromosomes Are paired along their lengths. Each gene on one homologue ia alined precisely with thâ¦e corresponding gene on the other homologue.
3. Explain how crossing over of chromatids in prophase I leads to genetic recombination, ensuring the gametes produced from one parent to be virtually all unique. During crossing over, homologous chromatids break and exchange equivalent segments, resulting in new combination of genes from the two parents.