Fern Plants Essay

1156 Words5 Pages
Evolution

Most botanists believe that the Pteridophytes also known as ferns are descendants of the Rhyniopsida, an extinct group of free-sporing plants which originated in the Silurian period (about 430 million years ago) and went extinct in the mid-Devonian period (about 370 million years ago).

Physiology

Ferns has no flowers, no seeds, and no fruits. A fern is defined as a cryptogam which means a plant that has no true flowers or seeds. With sporangia, a receptacle in which asexual spores are formed evolving from the leaf.

Physical characteristics

A fern plant generally consists of one or more fronds attached to a rhizome, which is a continuously growing horizontal underground stem. A frond is simply the leaf of the fern. The sizes of ferns and their fronds vary considerably among the different species.

The fern frond develops from a leaf bud referred to as a crozier. The crozier is coiled up in most species, with the frond apex at the middle of the coil. The reproductive cells of ferns are microscopic spores which are often clustered together in the brown spots visible on the fronds ' undersides.

Habitat and distribution

The majority
…show more content…
There are two distinct stages in the life cycle of ferns.Once the fertilization occurs, the adult fern will begin growing.The second stage in the life cycle of a fern is the adult stage. If direct sunlight falls onto the young fronds for an extended period of time, the plant may die easily. When the veins are matured, moisture from the ground will be transported easily to the outermost leaves and the plant can withstand periods of direct sunlight. After the plant is large and mature, it will grow spores on the undersides of its leaves and the life cycle of a fern will begin
Open Document