11. Three cells die and one that is most distant from the micropyle develops into the megaspore. 12. The micropyle opening allows the pollen ( a male gametophyte ) to enter the ovule for fertilization. 13. An obturator is present in the ovary of some plants, near the micropyle of each ovule. 14. Like the Nacophorini, their caterpillars have many setae on the ( vestigial ) prolegs of micropyle . 15. In chalazogamous plants, the pollen tubes enter the ovule through the chalaza instead of the micropyle opening. 16. It is an outgrowth of the placenta, important in nourishing and guiding pollen tubes to the micropyle . 17. Laser ablation of the border cells or their failure to migrate lead to improper morphogenesis of the micropyle . 18. A very small slit ( micropyle ) remains, meaning that the megasporangium is still exposed to the atmosphere. 19. The oocysts have a polar body and a prominent residuum but lack micropyles , sporocyst residua or Stieda bodies. 20. The top of the egg is depressed and forms a small central cavity called micropyle through which the egg is fertilised.
