Question

What is the main difference between Microphylls and Megaphylls?

Answer 1

Hint: A sporophyll is a leaf that contains sporangia. Sporophylls are present in both microphylls and megaphylls. In a plant, if the sporophyll bears megasporangia, they are called megasporophylls. If it bears microsporangia then it’s called microsporophylls. Sporophylls lead to the development of male and female gametophytes of seed plants (spermatophytes).

Complete answer:
Microphylls are the type of shortleaf, with single unbranched veins and no leaf gaps in the stele region as in moss or clubmoss. They also contain a single vein that is unbranched and derived from the prostate, again without having the leaf gap. Microphylls occur in lycophytes and horsetails. Microphyll origination is from the small projections called enations resulting in the single unbranched vein of microphyll.
Whereas megaphylls are the type of leaf with several large veins that branches apart or run parallel and are connected by a network of smaller veins.
Megaphylls contain multiple veins and leaf gaps too. They occur in angiosperms, gymnosperms, and the fronds of ferns. Megaphylls have evolved from a series of branches that lie close together on a stem, where the tissue gets flattened and forms the bench system tissue (parenchyma) joining the branches like webbing tissue.
                                     

Note:
In-plant anatomy and evolution, a microphyll is a type of plant leaf with one single, unbranched leaf vein. Plants with microphyll leaves occur early in the fossil record, and few such plants exist today. Megaphylls, in contrast, have multiple veins within the leaf and leaf gaps above them in the stem.