Why are lyes, horsetails and ferns classified as higher spore plants? Where do they grow? What is their structure?

Plunas, horsetails and ferns are classified as higher plants due to the presence of organs in them – a stem, leaves and a root. And they are called spores because they reproduce by spores.

Plaunas, horsetails and ferns grow mainly in humid shady places.

All ferns have stems, leaves and roots.

In lymphatics, the shoot branches dichotomously and divides into underground and aboveground parts. The root system is represented by adventitious roots, without root hairs. The leaves are small with one vein. Gametophytes (outgrowths) are small, green or colorless.

Horsetails grow in damp or wetlands. Aerial shoots have articulated stems with whorled branches extending from the nodes. The leaves are small, scaly, collected at the nodes in whorls. Silica crystals are deposited in the cells of the skin of stems and leaves, so the body of horsetails is very tough. Aboveground shoots of horsetail are formed annually from rhizome buds. The adventitious roots extend from the rhizome. Horsetail has two types of shoots. Spring shoots develop in early spring. They are light brown, non-photosynthetic. Spore-bearing spikelets are formed at the ends of spring shoots. The fern sporophyte is clearly subdivided into root, stem and leaf. The roots are always adventitious, the stem is usually well developed, sometimes modified and represented by a tuber or rhizome). Leaves are usually feathery, complex, they are called – vayi. The frond grows from the rhizome. On the underside of the frond, small brown tubercles – sporangia – develop. Young leaves are coiled like a cochlea. Sporangia are located on the underside of the leaf. The outgrowth (gametophyte) is often heart-shaped. It carries archegonia, antheridia and rhizoids.