Enteromorpha: Vegetative Body and Reproduction | Algae | Botany

In this article we will discuss about the vegetative body and reproduction of enteromorpha.  

Vegetative Body of Enteromorpha (Fig. 21):

At the very beginning the thallus is an uniseriate filament; very soon it becomes multiseriate and tube-like in appearance. The thallus is branched at intervals and exhibits some diversities of form. In a large number of species the thallus is attached to the substratum by means of rhizoids, while others, parti­cularly those inhabiting salt marshes, remain free-floating, either through­out their life or at least a part of it; one species (E. nana) possesses a basal prostrate region.

The bran­ching depends upon two major external factors,— the degree of salinity in the substratum and tempera­ture. It has further beer recorded that the thallus has got some power of regeneration. If any injury takes place near about the apex, papillate outgrowths appear from the injured cells, whereas if the basal region is subjected to an injury rhizoids are developed. The cells of the thallus are somewhat tubular, much longer than broad, and contain a number of chromatophores, with pyrenoids.

Reproduction in Enteromorpha:

Enteromorpha reproduces both asexually and sexually. The asexual reproduction takes place by means of zoospores, as in Ulva,. Each zoospore on germination gives rise to a new hap­loid plant. In the species (E. nana and E. procera) diploid zoos­pores are produced, and these are termed as neutrospores, or neu­tral spores.

Enteromorpha is heterothallic and the mode of sexual repro­duction is usually isogamous. An anisogamous type of reproduc­tion is, however, found in E. intestinalis, where the smaller gamete with a rudimentary pyrenoid is regarded as a result of fusion between two motile gametes a zygote is formed, which also remains motile for about an hour. After this period the fla­gella are withdrawn and the motility ceases, but the division of the zygote does not commence before several days.

In some species like E. clatharta there is no union of gametes. On the other hand, some of the cells of the gametangial region, which fail to divide and thereby give rise to gametes (rest cells) germinate afterwards developing into new haploid plants. These ultimately get detached from the parent plant and live as indepen­dent ones.

Enteromorpha exhibits an isomorphic alternation of generations.