Explanation:

Interphase is the phase in the cell cycle where the cell prepares for cell division by undergoing DNA replication. During this phase, the DNA in the cell is copied, resulting in two identical copies of each chromosome. So, if a cell in G1 of Interphase has 12 chromosomes, it means that there are 12 pairs of sister chromatids present in the cell.

Meiosis:
Meiosis is a specialized type of cell division that occurs in sexually reproducing organisms. It involves two rounds of cell division, resulting in the production of four haploid cells (gametes) from one diploid cell. Meiosis consists of two main stages: Meiosis I and Meiosis II.

Meiosis I:
During Meiosis I, homologous chromosomes pair up and exchange genetic material in a process called crossing over. This results in genetic variation in the offspring. In Anaphase-I of Meiosis I, the homologous chromosomes separate and move towards opposite poles of the cell.

Number of DNA molecules:
In Anaphase-I of Meiosis I, the homologous chromosomes separate, but the sister chromatids remain attached to each other. This means that each chromosome still consists of two identical DNA molecules, as they have not yet undergone replication.

Since the cell in G1 of Interphase has 12 chromosomes, it means that there are 24 sister chromatids present in the cell. Therefore, in Anaphase-I of Meiosis I, the number of DNA molecules per cell will be 24.

Conclusion:
In summary, during Meiosis I, the number of DNA molecules per cell remains the same as in Interphase since the sister chromatids have not yet undergone replication. Therefore, if a cell in G1 of Interphase has 12 chromosomes, there will be 24 DNA molecules per cell in Anaphase-I of Meiosis I.