micropyle

American  

[mahy-kruh-pahyl] / ˈmaɪ krəˌpaɪl /

noun

1. Zoology. any minute opening in an ovum through which a spermatozoon can enter, as in many insects.

2. Botany. the minute orifice or opening in the integuments of an ovule.

---

micropyle British  

/ ˈmaɪkrəʊˌpaɪl /

noun

1. a small opening in the integuments of a plant ovule through which the male gametes pass

2. a small pore in the shell of an insect's eggs through which the sperm passes

---

micropyle Scientific  

/ mī′krə-pīl′ /

1. A minute opening in the ovule of a seed plant through which the pollen tube usually enters.

2. A pore in the membrane covering the ovum of some animals through which a spermatozoon can enter.

---

Other Word Forms

• micropylar adjective

Etymology

Origin of micropyle

1815–25; micro- + Greek pýlē gate

Example Sentences

An opening called a micropyle allows entry of the pollen tube from the base.

From Textbooks • Jan. 1, 2015

When a pollen grain reaches the stigma, a pollen tube extends from the grain, grows down the style, and enters through the micropyle: an opening in the integuments of the ovule.

From Textbooks • Jan. 1, 2015

The micropyle allows the pollen tube to enter the female gametophyte for fertilization.

From Textbooks • Jan. 1, 2015

Three nuclei position themselves on the end of the embryo sac opposite the micropyle and develop into the antipodal cells, which later degenerate.

From Textbooks • Jan. 1, 2015

This is seen in the passion-flower, where the covering arises from the placenta or extremity of the funicle at the base of the ovule and passes upwards towards the apex, leaving the micropyle uncovered.

From Encyclopaedia Britannica, 11th Edition, Volume 11, Slice 3 "Frost" to "Fyzabad" by Various