Question

can you state how the content of the pollen sac come out

Answer 1

the mature Pollen Grain is a cell with double outer exam in urine time. it is it nucleus already divide into two nuclei and generating nucleus and tube nucleus. Pollen if it has fallen on the stigma for plant of the same species this is the Pollen Tube come out

Answer 2

The contents of the pollen sac come out when the pollen lands on the stigma and the pollen tube lead the male gametes to the ovary.The contents will come out with dehiscence of the anther . there is a line of dehiscence in the anther which separates theca once the pollen are formed.