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Trueman's Elementary Biology book I found says that the endoplasmic reticulum is absent in eggs, but no reason is given. Why is it absent?

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  • $\begingroup$ I did not know there was no endoplasmic reticulum in the eggs. Can you please add a reference we could easily check up? $\endgroup$ – Remi.b Nov 11 '15 at 15:35
  • $\begingroup$ I just found in my book. It might had initially but i thing it is reduced later .But I will try to add a reference $\endgroup$ – Chloritone_360 Nov 11 '15 at 15:58
  • $\begingroup$ I think there is some mistake, check [this] (sciencedirect.com/science/article/pii/S0012160699994459). It shows eggs (at least mammalian) have ER $\endgroup$ – Dexter Nov 11 '15 at 18:29
  • $\begingroup$ In addition, these Calcium waves produces by ER stores are way to block another sperm entry into egg. $\endgroup$ – Dexter Nov 11 '15 at 18:31
  • $\begingroup$ I THINK THE BOOK SAID ABOUT CHICKEN EGGS .. $\endgroup$ – Chloritone_360 Nov 15 '15 at 11:21
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I could find no indication that eggs are lacking an endoplasmic reticulum. On the contrary, I could find papers written on the ER in eggs of several species.

Mouse: The onset of activation responsiveness during maturation coincides with the formation of the cortical endoplasmic reticulum in oocytes of Xenopus laevis

Sea urchin: Structural changes of the endoplasmic reticulum of sea urchin eggs during fertilization

Human: The relationship between pregnancy outcome and smooth endoplasmic reticulum clusters in MII human oocytes

Frogs: The onset of activation responsiveness during maturation coincides with the formation of the cortical endoplasmic reticulum in oocytes of Xenopus laevis

However, as can be read in the sea urchin paper, the ER changes after fertilization:

We interpret these observations to indicate that in the first few minutes after fertilization, the egg's ER is fragmented

For other species, I could only find evidence that the ER reorganizes after fertilization because of changed calcium signaling needs

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