Explain Development of male
gametophyte.
Answers
Answer:
Development of Male Gametophyte
Explanation:
Pollen grains display germination that is initiated in pollen sac which is referred to as precocious germination wherein a large central vacuole formation causes the nucleus to be pushed to one side post which the nucleus goes through mitosis that gives rise to two daughter nuclei.
The small cell that is formed is known as the generative cell and the larger cell is known as the vegetative cell which has cytoplasm in sufficient amounts acting as a food reserve for the male gametophyte to develop, while the generative cell assembles at the mid-section of the pollen grain. At this phase, the pollen grains fall on the stigma wherein further development takes place.
The falling of the pollen grains on the stigma causes the nutrient absorption through the germ pore from the stigma which causes the vegetative cell to enlarge. The enlargement causes the intine to move out via the germ pore for the formation of the pollen tube.
The nuclei of the vegetative and generative cell travel to the pollen tube. The generative cell at this stage divides to produce two haploids, the non-motile and unicellular male gametes. For the deeper insertion of the tube, the size of the developed male gametophyte is diminished and derives the nutrition from the style’s tissues.
hope it helps..
Answer:
the male gametophyte containing the generative cell splits into two sperm nuclei , one of which fuses with the egg, while the other degeneration . after fertilization of the egg , the deploid zygote is formed , which divides by mitosis to form the embryo . the scales of th cones are closed during development of the seed