Are Psilotum heterosporous or Homosporous?

Psilotum is fern-like vascular plants, also known as whisk ferns. Most of them are homosporous, while some may be heterosporous. Explore more: Pteridophyta Classification.

Is Psilotum a true fern?

Psilotum is a genus of fern-like vascular plants, commonly known as whisk ferns. It is one of two genera in the family Psilotaceae, the other being Tmesipteris.

Which group of ferns are heterosporous?

Selaginella
significance in pteridophytes …all species of Selaginella are heterosporous; that is, they produce spores of two sizes, the larger designated as megaspores and the smaller as microspores. The megaspores develop into female gametophytes and the microspores into male gametophytes.

Do Psilotum and Equisetum appear to exhibit branching?

The sporophyte of Psilotum and relatives displays a dichotomic branching stem.

Are horsetails Homosporous or heterosporous?

LAND PLANTS The only extant genus, Equisetum (Equisetaceae) is herbaceous and homosporous. It has very small leaves that are more or less fused to form a dentiform leaf sheath at the node.

Are horsetails Homosporous or Heterosporous?

What plants are Homosporous?

Extant homosporous plants include most ferns and many lycophytes. The homosporous life cycle is an effective means for long-distance dispersal of species.

Why is Psilotum considered to be homosporous?

Psilotum is considered homosporous because the spores are produced in sporangia that are aggregated in groups of three on the ends of short, lateral branches.

What do the spores of a Psilotum look like?

The stems have many branches with paired enations, which look like small leaves but have no vascular tissue. Above these enations there are synangia formed by the fusion of three sporangia and which produce the spores. When mature, the synangia release yellow to whitish spores which develop into a gametophyte less than 2 mm (0.08 in) long.

What kind of plants are in the Psilotaceae?

It is one of two genera in the family Psilotaceae, the other being Tmesipteris. Plants in these two genera were once thought to be descended from the earliest surviving vascular plants, but more recent phylogenies place them as basal ferns, as a sister group to Ophioglossales.

What makes a Psilotum different from a Tmesipteris?

Psilotum. They lack true roots and leaves, the stems being the organs containing conducting tissue. There are only two species in Psilotum and a hybrid between the two. They differ from those in Tmesipteris in having stems with many branches and a synangium with three lobes rather than two.