The leaves and rhizomes of fresh ferns are protected by .........

Spores with chloroplasts are present in:

In ferns,spores are formed in

$A$ mature ligule,having a prominent basal portion,is called

Strobili or cones are found in

Apical growth of the lower vascular plants takes place by an apical cell. This cell is generally pyramidal. Though four-sided in shape,it is often referred to as a three-sided cell because