Question

Which one correctly describes reproduction and life cycle of fern?
A). Spore – Gamete – Prothallus - Sporophyte
B). Gamete – Spore – Prothallus - Plant
C). Prothallus – Sporophyte – Gamete – Fern
D). sporangia – Spore – Prothallus – Sporophyte – Plant

Answer 1

Amphimixis occurs during a cycle. Diploid parents produce haploid gametes that unite and become diploid adults, which repeat the cycle. This series of life stages and events that a sexually reproducing organism goes through is called its life cycle.

Complete answer:
During favourable months sporangia are produced on the underside or margin of leaves in ferns. After development, it becomes dry and bursts to release spores. These spores germinate on the acceptable substrate. Each spore absorbs water then ruptures and produces green filament which grows into prothallus (heart-shaped). Prothallus develops into a young sporophyte, which successively grows into an adult plant.
Life Cycle of fern completed in two phases:
Saprophyte is an agamogenesis and inside the sporangium spore mother cells are present.
Gametophyte may be an amphimixis and This stage involves male gametes called antherozoids and feminine gametes called eggs.

Hence the choice D is correct. sporangia – Spore – Prothallus – Sporophyte – Plant.

Note:
During favourable months sporangia are produced on the underside or margin of leaves in ferns. After development, it becomes dry and bursts to release spores. These spores germinate on the acceptable substrate. Each spore absorbs water,then ruptures and produces green filament which grows into prothallus (heart-shaped). Prothallus develops into a young sporophyte, which successively grows into an adult plant.