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I've found a website (Pearson's BioCoach) that claims centrioles duplicate in Prophase II. Is this accurate? Does it depend on the species in question?

Looking at three textbook illustrations of meiosis, none of their illustrations are consistent. All depict the movement and number of centrioles through Telophase I the same way: centrioles replicate in S of Interphase, then do their thing through Meiosis I. We end up at Telophase I with 2 centrosomes, each with 2 centrioles. There is one centrosome at either pole of the cell.

After that, the diagrams are unclear:

One text (general biology) seems to indicate either centrioles or entire centrosomes replicate after Telophase I, because Prophase II is shows both cells with 2 centrosomes, each with 2 centrioles.

Another (basic genetics) illustrates 2 daughter cells of Meiosis I inherit one centrosome each following Telophase I. In Prophase I, the centrioles in this centrosome splits, with one centriole going to either pole. Cytokinesis after Meiosis II results in 4 daughter cells, each with one centriole.

A third (more thorough genetics) stops depicting centrioles after Telophase I, instead showing the spindles growing in an aster formation from an empty space, the space where there were 2 centrioles up until Telophase I.

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  • $\begingroup$ Interesting question, I'm not sure that the answer is actually entirely known. Here's some articles that may interest you: one, two $\endgroup$ – canadianer Jul 14 '15 at 6:12
  • $\begingroup$ Indeed a nice one. The reality may not be exactly a duplicate, but varies in number - may be in terms of cancer. I am curious as well. You may take a look at this article as well. $\endgroup$ – bonCodigo Jul 14 '15 at 16:38
  • $\begingroup$ It makes sense that it would have to be in Prophase II or in an interphase between the two meioses; the kinetochores need to be captured by the microtubules during Metaphase II. Campbell's Biology has that a stage in Prophase II is formation of Spindle and migration of chromosomes towards the metaphase II plate late in prophase II. If you look at an upper level textbook they will have a phase between telophase I and prophase II called Interkinesis. It is similar to Interphase in Mitosis, but without the duplication of chromosomes. So it is likely in interkinesis that centrioles double. $\endgroup$ – AMR Sep 18 '15 at 16:28
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When a cell enters the cell cycle and passes through S phase, each centriole is duplicated. A "daughter" centriole grows out of the side of each parent ("mother") centriole. Thus centriole replication — like DNA replication (which is occurring at the same time) — is semiconservative.

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  • $\begingroup$ Centrioles migrate to opposite poles at the end of meiosis and then the centrioles duplicate in the new cell and during the S phase. One centriole grows from the parent centriole. Therefore, like in DNA replication the centriole replication is semi-conservative. $\endgroup$ – Patty Belloise Sep 18 '15 at 15:00
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    $\begingroup$ You are correct about the replication being a result of a semiconservative mechanism, however the question is asking about the duplication between Meiosis I and II. There isn't a synthesis phase in this period. Consider adding a reference an incorporating your comment into the answer, as it is likely that most people are not aware that Centriole replication is via a semi conservative mechanism. $\endgroup$ – AMR Sep 18 '15 at 16:34
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A reference from my book -

Interkinesis or Intrameiotic Interphase

It is metabolic stage between telophase of meiosis I and prophase of meiosis II. Chromosome are elongated but chromatin reticulum is not formed. Protein and RNA synthesis may occur. Centrosome or centriole pairs undergo replication in animal cells. However, there is no DNA synthesis. It is important for bringing true haploidy (haploidy of DNA) in daughter cells.

From this site - https://openoregon.pressbooks.pub/mhccmajorsbio/chapter/meiosis-ii/ (search for centrosomes in that page)

The centrosomes that were duplicated during interkinesis move away from each other toward opposite poles, and new spindles are formed.

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