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SEXUAL REPRODUCTION AND VEGETATIVE MORPHOLOGY OF FUNARIA

Funaria is a common terrestrial moss which grows in the form of bright green variety patches in shady and damp places. The genus comprises of 117 species. Funaria hygrometrica is most common and world wide species. It colonizes burnt soil and grows best in the presence of calcium, potassium, and nitrogen and phosphorous.
Vegetative Morphology
Thales: Funaria plant is a gametophyte and the plant body is differentiated into prostrate, green, branched filamentous structure, the prostonema which give rise to erect leafy shoot called gametophores. Protonema is short lived, therefore a transitory structure. The adult plant consists of gametophores only. Each gametophore is differentiated into stem and leaves. They bear sex organs at their apices. Rhizoids arise from the base of each gametophore which anchor it into the soil and absorb moisture and nutrients. The leaves are small, oval, sessile and green. The leaves borne on prostrate branches and on lower portion of an erect branches are colourless and scale like, whereas the leaves on upper portion of an erect branches are green and larger in size. These are called foliage leaves and are spirally arranged. The leaves also surround sex organs. These leaves are larger in size and different in shape.
Internal Organization: Internally the stem is differentiated into a central cylinder of elongated living cells, the leptoids; or empty cells, the hydroids. Both these cells are considered to be conducting in nature; the hydroids conduct water and the leptoids food. Outer to central cylinder, there is a many layered cortex composed of thin walled cells. The younger cells contain chloroplasts. The cortex contains leaf traces running from leaves to central cylinder.
The leaf lamina consists of a single layer of parenchyma except in the midrib region where it is composed of elongate, thick walled cells, the steroids.
Reproduction __ Gametophyte
Funaria gametophyte reproduces by vegetative multiplication and sexual reproduction.
Vegetative Multiplication: The vegetative multiplication takes place in a variety of ways such as:
The prostrate branches die and erect branches grow as independent plants.
Small gemmae develop in groups along the midrib of leaves or at the tips of stem. Each gammae develop into a new plant.
A spore germinates into primary protonema, which breaks up into fragments by death of cells. Each fragment develops into a new protonema , from bud and gives rise to gametophores.
In some cases the sporophyte tissue is wounded and produces a protonemas. The bud develops on it and each bud grows into a diploid gametophores. This is apospory.

SEXUAL REPRODUCTION IN FUNARIA
Sexual Reproduction: Funaria spp are monoeclous. The sex organs, antheridia and archegonia develop at the apices of seprate erect branches called gametophores. The sex organs are intermingled with 4-6 cells high and one cell wide sterile hair called paraphyses. The paraphyses cells contain chloroplasts and the apical cell of each paraphyses is globose and meet over an antheridium to protect it. The paraphyses also hold water by capillary and help prevent desiccation.
Male Branch: Antheridia develop in group at the expanded convex shaped apex of leafy gametophores called male branch. The antheridia are intermingled with paraphyses and surrounded by leaves, the perichaetal leaves that form an envelope know as perichartium.
Structure and Development of Anhteridium:  A mature antheridium is club shaped and born on a stalk. The main body contains a mass of spermatogenesis cells surrounded by a layer of jacket cells. The free distal end of the antheridium is differentiated into a cap-like structure, the operculum. It helps in dehiscence.
Each antheridium develops from superficial cells of apex which becomes papillate and divide to form outer and inner cells which give rise to lower embedded part of the stalk. The outer cell divides by transverse divisions to produce a filament of 2-3 cells. The terminal cell of the filament differentiates into apical cell with two cutting faces. It cuts off 5-15 segments arranged in two rows. A segment, 2-3 cells away from the apical cell, divides into a smaller jacket initial, and a larger primary spermatogenous cell which cuts off a second jacket. The primary spermatogenous cells undergo repeated division to produce sperm. The epical cells differentiate into operculum.
Female Branch: The gametophores bearing archegonia is called female branch. It arises from the base of male branch. The spex of the branch flattens into a receptacle on which archegonia develop on clusters intermingled with paraphyses.
Structure and Development of Archrgonium: A mature archegonium is flask shaped which is borne on short stalk. It has a basal swollen part of venter and elongated neck. The venter is surrounded by a two layered jacket whereas the jacket around the neck is singled layered. 
Archigonium develops from an apical cell with two cutting faces. It cuts off 4-8 segments which develop into stalk. Afterward the apical cell becomes three sided and cuts off three peripheral cells surrounding an axial cell (the former apical cell). The peripheral cells divide to form jacket initials which divide to form jacket layers around the venter and neck. The axial cell divides to form primary cover cell and central cell which divides to form primary canal cell which give rise to neck canal cells, and venter cell. The venter cell divides to produce vecter canal cell and an egg.
Fertilization and Past Fertilization Changes: Rain water or dew collect at the apical end of the male branch cause deshiscence of antheridium. The jacket cells imbibe water and split open at operculum forming a pore. The male sperms move out in a mass. At the same time neck canal cells and venter canal cell disintegrate to form mucilage. It absorbs moisture, swells up and forces disintegration of apical cells of the neck. The male sperms are attracted chemotacticially, swim to archigonium, enter it and one of these succeeds in fertilizing the egg to form the zygote.
The zygote enlarges in size to fill up the venter and secretes a thick wall around it. The stimulus of fertilization initiate divisions in the cells of venter which form protective sheath called calyptras around the developing sporogonium.

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