Pollen grains received by the stigma germinate and give rise to pollen tubes. Only one pollen tube finally reaches the embryo sac. This tube will have two male nuclei, which migrate to the tip of the pollen tube at the time of fertilisation.
Usually pollen tube enters the ovule through micropyle. The tube discharges the two male gametes into its embryo sac. Let`s start drawing the process. Here we go.
1. Draw a oval shape and make a vertical line as shown in first step.
2. Erase the bottom and draw outer integuments of ovule.
3.Draw inner integument and embryo-sac as shown.
4. Extend the funicle of ovule as shown, this should be connected to ovary later.
5. Draw the ovary around the ovule and extend to style and stigma as shown.
6. Draw outer covering of ovary and style to represent thickness of ovary.
7.Draw pollen grains on stigma and extend a fine line along the style towards
the micropyle to represent pollen tube like a maze puzzle.
8.Draw another parallel curve along the original curve as shown and make two dots
at the tip of pollen tube to represent two male gametes.
9. Label the parts neatly as shown.
Share it Now!
4 comments:
this was really helpful,thanks a ton!! :)
:) ;)
please apload how to draw pollen grain easyly
That was really helpful
I recommended to to all my frnds
I really appreciate your hard work
;)
Post a Comment