In this article we will discuss about the origin of seed in selaginella. An evolutionary sequence of origin of seed from homosporous form should involve: (a) Production of two kinds of spores, (b) Reduction in the number of functional megaspores, (c) Final reduction to a single megaspore in the sporangium, (d) Retention of megaspore within the megasporangium, (e) Elaboration of [...]
In this article we will discuss about the process of reproduction in selaginella with the help of diagram. Selaginella is heterosporous. Two types of sporangia (larger ones megasporangia and smaller ones microsporangia) containing larger and smaller spores are borne on sporophylls which form cones terminally either on the stem or branches. The cones are inconspicuous due to small size and [...]
In this article we will discuss about the anatomy of selaginella with the help of a suitable diagram. Apical growth takes place by a single cell and its derivatives or by an apical meristem, comprising a group of cells. Branching occurs by a bifurcation of shoot apex into two apices, one of which overtops the other resulting in anistomous branching. [...]