Bryophytes include various mosses and liverworts that commonly grow in moist shady areas in the hills. The plants are land inhabiting or terrestrial. They complete their vegetative phase on land but water is necessary for their sexual reproduction. So bryophytes are known as “amphibians of the plant kingdom'’. The main plant body of the bryophyte is a haploid.
Characteristics of Bryophytes
- Water is necessary for the act of fertilization, i.e., bi-flagellated antherozoids swim across the film of water.
- True roots are absent. Instead unicellular (Riccia, Marchantia) or multicellular (Funaria) rhizoids are present.
- Vascular tissues are absent. So the name Atracheata has been given by Oswal Tippo.
- Sex organs are multicellular and jacketed. They are male antheridium and female archegonium.
- Archegonium is flask-shaped with a tubular neck and a swollen venter. The wall of the venter divides periclinal to form a protective covering called calyptra.
- Sexual reproduction is of oogamous type. Fertilization produces an embryo inside the archegonium, which grows into a sporophyte.
- The sporophyte of sporogonium is parasitic over the gametophyte. It is differentiated into foot, seta, and capsule(although only capsule in Riccia). Spore is produced inside the capsule. Bryophytes are homosporus.
- Bryophytes show heteromorphic or heterologous alternation of generation in the life cycle.
