• Evan after killing the generative cell with a laser beam , the pollen grain of a flowering plant germinates and produces normal pollen tube because
• laser beam stimulates pollen germination and pollen tube growth
• laser beam dose not damage the region from which pollen tube emerges
• the contents of the killed generative cell permit germination and pollen growth
• the vegetative cell has not been damaged

A pollen grain has two type of cell in it. The generative cell and the vegetative cell. When this pollen lands on a compactable stigma, the generative cell develops into 2 male gametes (in angiosperms) and the vegetative cell develop into pollen tube. Since the laser only killed the generative cell only the male gametes die, but the pollen tube will grow out as the laser have not damaged the vegetative cell. Option (4)

 

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