Question

Which one correctly describes reproduction and life cycle of fern?

• A. Spore $\to$ Gamete $\to$ Prothallus $\to$ Sporophyte
• B. Gamete $\to$ Spore $\to$ Prothallus $\to$ Plant
• C. Prothallus $\to$ Sporophyte $\to$ Gamete $\to$ Fern
• D. Sporangia $\to$ Spore $\to$ Prothallus $\to$ Sporophyte $\to$ Plant

Answer 1

The correct option is D Sporangia $\to$ Spore $\to$ Prothallus $\to$ Sporophyte $\to$ Plant


During favourable season, sporangia are produced on the underside or margins of leaves in ferns in clusters called sori. After development, the sporangium dries up and bursts to release spores. These spores germinate on suitable soil. Each spore absorbs water, then ruptures and produces a green filament which grows into the gametophyte called prothallus (heart-shaped). The prothallus has the antheridium and the archegonium, which produce the gametes, i.e. the sperm and egg, respectively. The sperm swims to and fertilizes the egg to form a diploid oospore. The oospore develops into the young sporophyte, which in turn grows into an adult plant.
Hence, the correct sequence is: Sporangia $\to$ Spore $\to$ Prothallus $\to$ Sporophyte $\to$ Plant