Definition of micropyle in English:

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Pronunciation: /ˈmʌɪkrə(ʊ)pʌɪl/


1 Botany A small opening in the surface of an ovule, through which the pollen tube penetrates, often visible as a small pore in the ripe seed.
Example sentences
  • It remains to be studied exactly how the pollen tubes reach the micropyle of the ovules.
  • However, pollen tubes from control pollen showed normal morphology when growing towards the micropyle of an ovule in a HTS plant.
  • Within the ovary, pollen tubes also grew in the ECM to penetrate the micropyle and subsequently grew intercellularly within the nucellus up to the embryo sac.
1.1 Zoology A small opening in the egg of a fish, insect, etc., through which spermatozoa can enter.
Example sentences
  • Coupling these screens with a visual assessment of seed formation has yielded mutants defective in FG development or in the ability of pollen tubes to release their sperm after entering the micropyle.
  • In a favorable situation, an opening called the micropyle appears and releases amoebocytes, which differentiate into cells of all the other types.
  • Each cupule is recurved, has a lip-like projection near the point of attachment, and contains several ovules arranged in a curved row with their micropyles facing the cupule opening.


Early 19th century: from micro- 'small' + Greek pulē 'gate'.

For editors and proofreaders

Line breaks: micro|pyle

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