Why must the plant which grows directly from the fern spore be wet? so that the egg can be fertilized so that it can grow in order to produce a seed

Sperm have flagella, which are whip-like tails that allow them to swim. In order to swim, they need water. This means ferns can only successfully reproduce in wet places, or after a rain. After fertilization, the sporophyte grows up on top of the gametophyte.

An autotrophic protist - they can perform photosynthesis and mainly consist of unicellular algae. they can be divided into number of systematic group according to the shape of their cell and the type of photosynthetic pigments they use.