Nevertheless, most lyginopteridalean ovules retained a lagenostome, despite its function in pollen capture having been replaced by the micropyle.
22.
In a favorable situation, an opening called the micropyle appears and releases amoebocytes, which differentiate into cells of all the other types.
23.
They can only access the kernel when the shell has been previously damaged by another insect or when a nut has an open micropyle.
24.
In non-flowering seed plants, pollen germinates in the pollen chamber, located beneath the micropyle, underneath the integuments of the ovule.
25.
When placed on the ovary, and makes its way along the placenta, guided by projections or hairs, to the micropyle of an ovule.
26.
The integuments do not enclose the nucellus completely but retain an opening at the apex referred to as the "'micropyle " '.
27.
The pollen grain then takes in moisture and begins to germinate, forming a pollen tube that extends down toward the micropyle opening in the ovule.
28.
For the process of pollination to be successful, a pollen grain produced by the micropyle and fertilise it, resulting in the production of a seed.
29.
The upper or chalazal pole becomes the main area of growth of the embryo, while the lower or micropylar pole produces the stalk-like suspensor that attaches to the micropyle.
30.
Each egg contains a number of micropyles, or tiny funnel-shaped openings at one end, the purpose of which is to allow sperm to enter and fertilize the egg.
