Dominance of the sporophyte in ferns when compared to the same structure in mosses??

Question

What characteristics show the dominance of the sporophyte in ferns when compared to the same structure in mosses? Why are ferns found only in moist environments?

thanks!!

Answer 1

A fern plant is a sporophyte and they can be rather large plants, it alternates with a prothallus which is so tiny it fits on a microscope slide. The prothallus is the gametophyte.  In mosses the green leafy plant is a gametophyte, the sporophyte actually grows from the plant and is dependent on it for nutrition since it isn't photosynthetic.

Both ferns and moss rely on water for reproduction because they have a swimming sperm that must reach the egg.  So they need a moist enviroment to carry out the life cycle.

Answer 2

Yes ! The fern sporophyte is the dominant phase in the fern life cycle AND  as compared to the similar structure in moss life cycle it is WELL DEVELOPED .

Now let us look at it minutely ========

Question 1 ) What characteristics show the dominance of the sporophyte in ferns when compared to the same structure in mosses?

Answer 1 ) (i)A mature , diploid sporophyte of fern is having its own roots, stem (Rhizome ) and leaves ( Compound ).

(ii) It has its own vascular elements ( Xylem and Phloem ) .

(iii) Nutritionally it is independent at maturity and autotrophic due to presence of photosynthetic tissue .

(iv) it can perennate it self for many years !!!

IN CONTRAST, THE MOSS SPOROPHYTE IS ====

(i) With out its own roots , stem and leaves .

(ii) Does not have vascular elements for conduction ( Xylem and Phloem).

( iii) Nutritionally it is NOT independent and permanently attached to the gametophyte( The moss plant ) by its FOOT !!!

It draws nourishment from the gametophyte ( The moss plant ). So it is a parasite on the gametophyte generation !!!

(iv) It has short life and can not prolong it .

The comparison made above between the Sporophyte of Fern and The Sporophyte of Moss shows the superiority of Fern sporophyte over that of moss sporophyte .

Question 2 )Why are ferns found only in moist environments?

Answer 2 )  Ferns are found in the moist environment for two reasons .

( I ) The fern sporophyte ; eventhough well developed ; does not have provision to protect from excessive  transpiration and harsh , direct sun light .

( I I ) The gametophyte ( The prothallus ) is entirely water dependent !!!

From = A Botanist