Final answer:
After the first round of division in meiosis, called Meiosis I, the amount of DNA in a person's sex cells becomes equal to the amount of DNA in one of their G1 phase kidney cells.
Step-by-step explanation:
In meiosis, the amount of DNA in a person's sex cells becomes equal to the amount of DNA in one of their G1 phase kidney cells after the first round of division, which is called Meiosis I. During Meiosis I, homologous chromosomes separate, resulting in two daughter cells, each with half the amount of DNA as the parent cell. Therefore, the amount of DNA in the sex cells is reduced by half, making it equal to the amount of DNA in a kidney cell.