PTERIDOLOGY SELAGINELLA

Introduction
In this section we are going to discuss about the reproduction of Selaginella. Selaginella reproduce manily two ways Vegitative Reproduction and sexual reproduction
Vegitative Reproduction
In vegitative Reproduction mainly 4 processes are takes place
* Fragmentation
* Dormant buds
* Bulbils
* stem-tubers
Fragmentation
* During favorable conditions
* Prostate branches produce roots
* These branches brake
* New sporophyte produced
Dormant buds
* Produced in areal branches
* During favorable conditions
* Develop in to new plant
Stem-tubers
* Produced at the apices of areal branches
* During favorable conditions 
* Develop in to new sporophytic plant body
                                                                         
Sexual Reproduction
Sexual reproduction occurs by formation of spores. Selaginella is heterosporous, which produce two types of spores.
Megaspores and Microspores
 
                  V.S of Selaginella strobili

* Sporophylls are generally arranged spirally around a central axis
* Each strobilus consists of microsporophylls and megasporophylls
* Generally microsporophylls are arranged in the top of strobilus
* Megasporophylls are in the bottom
* Microsporophyll has a leg you like structure and at the base microsporangium is present
* Microsporangium has many microspore mother cell
* Each microspore mother cell undergo meiosis and mitosis
* Microsporangium produce large number of microspores
* Megasporophyll consist of leg you like structure and a a bottom megasporangium
* Megasporangium has many megaspore mother cell
* But only 1 megaspore mother cell is get functioned
* This megaspore mother cell produce for haploid megaspores
Structure of mega & microspores
* Mega and microspores has small stock and a capsule
* This capsule has two layers
* These layers are called jackets
* Outer layer of cells are elongated and a contains chloroplast
* The chloroplast done photosynthesis
* In the layer is the tapetum
* Tapetum is the nutritive layer that nourish the developing spores
Microsporangium : microsporangium has many haploid microspores
Megasporangium : megasporangium 1-4 megaspores are developed and they are functioned
 
                  V.S of microsporangium & megasporangium

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