Which one of the following is heterosporous?

Options

A. Dryopteris
B. Salvinia
C. Adiantum
D. Equisetum

Answer

B

Explanation

(b) From the following Salvinia is heterosporous. Heterospory is the production of spores of two different sizes and two different developmental patterns. Small spores are called microspores and larger as megaspore. Microspores germinate to produce the male gametophyte or microgametophyte that bear male sex organs while, megaspore germinates to form female gametophyte or megagametophyte taht bears archegonia or female sex organs . It is most important evolutionary development in the vascular plants because it has ultimately lead to seed development, e.g. Selaginella, Marselia, Salvinia, Azolla, Isoetes. Dryopteris is homosporous and 32-64 haploid spores are produced in each sporangium. Adiantum is also homosporous. The spores are the pioneer structures of the gametophytic generation.