Final answer:
The G1 and G2 phases of mitotic interphase are missing from meiotic interkinesis. Interkinesis in meiosis is an abbreviated rest period without the cell growth and prep for DNA synthesis that occur in mitotic interphase.
Step-by-step explanation:
The phase(s) of mitotic interphase that is missing from meiotic interkinesis is both the G1 and G2 phases. Interphase in mitosis includes three subphases: the G1 phase (First Gap), S phase (Synthesis of DNA), and G2 phase (Second Gap). During interphase, cells undergo growth, DNA replication, and preparation for cell division. The G1 phase is focused on cell growth and accumulation of resources necessary for DNA synthesis. In the S phase, the cell replicates its DNA. Finally, in the G2 phase, the cell makes final preparations for cell division by reorganizing its cell contents and structures.
Meiosis I is preceded by a similar interphase of G1, S, and G2, but after Meiosis I, cells enter interkinesis which lacks those complete stages of interphase. Interkinesis is generally a shortened rest period that does not always include a G1 phase or a G2 phase at all. This is due to the fact that the cells are not preparing for further DNA synthesis. Instead, Meiosis II promptly follows interkinesis to separate the sister chromatids into gametes. This is a sharp contrast with mitosis, where cells complete the full interphase before entering mitotic division. The eliminated phases in meiotic interkinesis serve to expedite the process of gamete formation without the need for additional growth or DNA synthesis that would occur during the complete interphase of mitosis.