The number of male prothallial cells in $Selaginella$ is:

$A$ fern prothallus is bisexual. If fertilization takes place between the gametes produced by the same prothallus,then it is known as:

Which of the following is a heterosporous plant?

The rhizophore in $Selaginella$ is:

Heterospory,i.e.,the formation of two types of spores—microspores and megaspores—is a characteristic feature in the life cycle of a few members of pteridophytes and all spermatophytes. Do you think heterospory has some evolutionary significance in the plant kingdom?

Which has vascular tissue,produces spores but does not have seeds?