Biological explanation : Germination of a seed will stop if the micropyle is closed.
Answers
Answer:
The Micropyle is a differentiated area of surface in an egg through which a sperm enters.its a small opening present at the tip where the integument which does not cover the nucellus(central lart of ovule containing embryo sac)present in the ovule. Pollen tube generally enters the ovule through a micropyle in most angiosperms. It is present as a small pore above the hilum in the seed. It absorbs water and helps in seed germination.
Explanation:
A tiny pore micropyle is situated close to the hilum. It marks the opening through which the pollen tube had entered the ovule.
Actually Micropyle serves two functions:
(1) When soaked in water the seeds absorb water mainly through this micropyle and the
available water activates the enzymes present in seed and the embryo present in seed thus gets germinated.
2) Micropyle the tiny pore aids the diffusion of respiratory gases generally (CO2 and O2) for the growing embryo.
3) The opening of the micropyle allows the pollen to enter the ovule for fertilization. In gymnosperms (e.g., conifers), pollen is drawn into the ovule by a drop of fluid that flows out of the micropyle. Subsequently, the micropyle closes. Only a pollen tube enters the micropyle in angiosperms. The radicle of the seedling emerges through the micropyle during germination.
4) Micropyles are also found in microorganism sporozoites such as Plasmodium in the anterior part of the cell that ultimately leads to the apical cap.
And if the micropyle is closed the above functions would not occur which are necessary for fully functioning seed.