Where does the pollen tube enter?

The pollen tube ultimately enters an ovule through the micropyle and penetrates one of the sterile cells on either side of the egg (synergids).

Does the pollen tube enter the embryo sac?

The pollen tube enters into the embryo sac at the micropylar end. This entry may be between egg and one synergid or between wall of embryo sac and synergid or through one synergid.

How many types of pollen tubes are there?

A pollen tube consists of three different regions: the apex which is the growth region, the subapex which is the transition region, and the shank which acts like normal plant cells with the specific organelles. The apex region is where tip growth occurs and requires the fusion of secretory vesicles.

How does the pollen tube enters the embryo sac during double fertilization?

Double fertilization occurs by two male gametes. One male gamete fuses with the female egg cell in the micropylar end. The pollen tube which has male gametes enters the embryo sac through the nucleus and then from the micropylar end it penetrates , between the egg cell and synergid.

Where is the embryo sac?

The megagametophyte, or embryo sac, is situated within the body of nucellus parenchyma cells, which are covered by the integuments (Figure 1A).

Which one guided the entry of pollen tube?

Synergids
Synergids secretes chemical; which guide the pollen tube. Synergids are present in the embryo sac, and it enters the ovule sac through the micropyle.

How does the pollen tube enter the embryo sac during double fertilization?

The pollen tube is guided by the chemicals secreted by the synergids present in the embryo sac, and it enters the ovule sac through the micropyle. The fertilized ovule forms the seed, whereas the tissues of the ovary become the fruit, usually enveloping the seed.

How many pollen tubes emerge from a pollen grain?

Only a single pollen tube emerges from a pollen grain that contains pollen nuclei. Pollen tube helps the nuclei to reach the ovule. there fertilization takes place.

What does the pollen tube carry?

In compatible pollination, pollen tubes carrying two sperm cells grow through the pistil transmitting tract and are precisely guided to the ovules, discharging the sperm cells to the embryo sac for fertilization.

How many number of nuclei are involved in double fertilization?

five
Hence, the total number of nuclei involved in double fertilisation are five.