Tag: botany

Bryophytes are the non-vascular terrestrial plants of moist habitats in which a multicellular diploid sporophyte lives as a parasite on an independent multicellular haploid gametophyte. Bryophytes include the mosses and liverworts that are found commonly growing in moist shaded areas in the hills. The plant body of bryophytes is more differentiated than that of algae. It is thallus-like and maybe prostrate or erect. They lack true roots. The plant body is attached to the substratum by root-like structures called rhizoids. The rhizoids may be unicellular or multicellular.

Xylem and phloem are vascular tissues which are a complex conducting tissue formed of more than one type of cell. Xylem transports water and minerals while phloem conducts organic food. Bryophytes do not have to conduct tissues. They are non-vascular terrestrial plants of moist habitats in which a multicellular diploid sporophyte lives as a parasite on an independent multicellular haploid gametophyte. Pteridophytes are the first terrestrial plants to possess conducting tissues.

Bryophyta is known as amphibians of the plant kingdom as they can survive both on land and water. They lack fully developed vascular tissue. They do not have true roots rather they have a root-like structure known as rhizoid. They originate from lower epidermal cells of bryophytes. They are similar in function to root as it helps in the absorption of water.

Bryophyta acts as the connecting link between algae (Thallophyta) and Pteridophyta. Their body is differentiated more than algae but lacks true root, stem, and leaves. They do not have vascular tissue like algae but have multicellular sex organ and requires water for fertilization like Pteridophyta.

The first land inhabiting plants are bryophytes.
The evolution of plants has resulted in widely varying levels of complexity, from the earliest algal mats, through bryophytes, lycopods, ferns to the complex gymnosperms and angiosperms of today.  bryophytes (liverworts, mosses and hornworts) have developed the gametophyte, with the sporophyte becoming almost entirely dependent on it; vascular plants have developed the sporophyte, with the gametophyte being particularly reduced in the seed plants.

Amphibians are those organisms which live on both land and in water. Bryophytes are called amphibians of the plant kingdom because these plants, though they live in soil, they need water for sexual reproduction. The sperm of bryophyte (antherozoids) are flagellate and need water to swim to the eggs. In other words, as these plants need water for reproduction unlike other plants, they are called as amphibians. 

Funaria is a genus of approximately 200 species of moss. These are primitive multicellular, autotrophic, shade-loving, amphibious plants. They reproduce by spore formation. They have no vascular system. Conducting tissue present is parenchyma. Root like structures called rhizoids are present. They show alternation of generation i.e., the gametophytic stage alternates with the sporophytic stage.

Bryophytes are considered the first group of land plants, having evolved from aquatic ancestors to colonize terrestrial environments.