THE AMPHIBIANS OF PLANT KINGDOM
Bryophytes are non-vascular terrestrial plants of moist habitats. They possess a multicellular diploid sporophyte, which lives as a parasite on an independent multicellular haploid gametophyte. This gametophyte develops multicellular jacketed sex organs. These plants are very small and cosmopolitan They are classified as Atracheata' as they lack a vascular tissue. They must rely on slow diffusion opoorly developed conducting tissues to distribute water and other nutrients. Primarily they are terrestrial, grow in moist and shady places, such as damp walls, damp soil, on banks of river and pond, eto Fertilisation is zooidogamic and water is necessary for it.
General Characteristic
. None of the bryophyte have truevascular (i.e. xylem and phloem)and lignified tissue. Many mosses have special water conducting cells called hydroids in the centre of the stem and few have food conducting cells called leptoidssurrounding thehydroids. Most water is absorbeddirectly through the surface.
The plant body lacks the true roots stems and leaves. It grows prostrate on the ground. It is attached to the substratum by delicate, unbranched, unicellular, hair like structures called rhizoids. Higher bryophytes have erect body. It consists of a central axis which bears leaf-like expansions. It is attached to the subst- ratum by branched multicellular rhizoids. . The plants are small. They seldom attain great length or height. The maximum height is 60 cm fora moss species growing in New Zealand.
