A cell preparing to undergo meiosis duplicates its chromosomes during
View Available Hint(s)
meiosis II.
interphase.
metaphase 1 .
anaphase I.
prophase I.
The Correct Answer and Explanation is :
Correct Answer: Interphase
Explanation:
Before a cell undergoes meiosis, it goes through a preparatory phase called interphase, during which the chromosomes are duplicated. Interphase is not part of meiosis itself but is a crucial precursor stage in the cell cycle. It ensures that each chromosome consists of two identical sister chromatids, which are held together at a central region called the centromere.
Breakdown of Interphase:
- G1 Phase (Gap 1):
The cell grows, synthesizes proteins, and prepares for DNA replication. This phase ensures the cell is ready for the duplication process. - S Phase (Synthesis):
DNA replication occurs during the S phase. Each chromosome is duplicated, resulting in two sister chromatids for every chromosome. This step is vital because meiosis requires a sufficient amount of genetic material to ensure proper distribution into the resulting gametes. - G2 Phase (Gap 2):
The cell undergoes further growth and checks for errors in DNA replication. It also produces the proteins and organelles needed for the division process.
Why Interphase is Important:
Interphase is critical for meiosis because meiosis involves two rounds of division: meiosis I and meiosis II. Without chromosome duplication in interphase, there would not be enough genetic material to properly segregate into the four resulting haploid cells.
Why Not the Other Options?
- Meiosis II: This phase separates sister chromatids but does not involve chromosome duplication.
- Metaphase I: Chromosomes align in the center of the cell during meiosis I but are already duplicated.
- Anaphase I: Homologous chromosomes separate but do not duplicate.
- Prophase I: Chromosomes condense and form tetrads, but duplication has already occurred during interphase.
In summary, interphase is the phase where chromosomes duplicate in preparation for meiosis, ensuring the correct genetic material is passed on to the gametes.