Question

Even after killing the generative cell with a laser beam, the pollen grain of a flowering plant germinates and produces normal pollen tube because

• A. laser beam stimulates pollen germination and pollen tube growth.
• B. the laser beam does not damage the region from which pollen tube emerges.
• C. the contents of killed generative cell permit germination and pollen tube growth.
• D. the vegetative cell has not been damaged.

Answer 1

The correct option is D the vegetative cell has not been damaged.

Each microspore formed at the end of microporogenesis undergoes asymmetric mitosis to form a large vegetative cell and a smaller generative cell suspended inside the vegetative cell.

Generative cells undergo futher mitosis to form two male gametes.

The vegetative cell is larger and metabolically more active than the generative cell. Its function is to form the pollen tube which comes out of the germ pore after pollination and transports the male gametes into the female gametophyte.

Hence, killing the generative cell will not hamper the pollen tube germination. Fertilisation process is hampered as male gametes are not available in the absence of generative cells.