Its contents are metamorphosed into a single antherozoid. Antheridial FilamentĪttached to the primary or secondary capitula are several branched uniseriate filament called as antheridial filament. The inner ends of manubrial cells are united to form eight isodimetric cells called as primary capitula Secondary capitulaĮach primary capitula has one or two smaller cells towards the cavity of globule called as secondary capitula. On the inner side of shield-cells in the center is attached an elongated cell called as manubrium. The outer wall of each shield cell has radial out growth therefore it appears as multicellular structure. It extends within the cavity of the globule and join with the primary capitula Shield cellsĮach globule is in the form of ball like structure whose wall consists of large plate like eight cells called as shield cells. The globule is attached to the plant by a large cell called as pedicel cell. The mature globule is bright yellow in color. The male fructification is called as globule. The monoecious species are protandrous, i. Some species are dioecious while the others are monoecious. These specialist complex structures containing the sex organs are called globule (male fructification) and nucule (female fructification). In antheridia and oogonia that are enveloped in multicellular sheaths formed of cells derived from the cells present below the sex organs. The sexual reproduction is an advanced type of oogamous sexual reproduction. These are called secondary protonema and develop into new plants like primary protonema. Secondary Protonema: In some cases, protonema-like outgrowths arise from the node of primary protonema or from the basal cell of the primary rhizoid. These develop into new plant on detachment. After being detached these develop into new plants.īulbils: These are small, rounded or star-shaped, tuberous bodies that develop either on rhizoids ( Chara aspera) or on stem nodes ( Chara baltica). The common means of vegetative reproduction are as followings:Īmylum Stars: These are star-shaped groups of cells developed from the lower nodes. The vegetative reproduction in Chara involves various kinds of reproductive bodies which on detachment from the parent plant give rise to a new plant. Asexual reproduction by spore formation is absent. The Chara reproduces by vegetative and sexual reproduction. Each peripheral cell cuts off apical cells of branches of limited growth. The nodal initial divides by vertical divisions intersecting each other to produce two central cells surrounded by 6-20 peripheral cells. The internodal initial elongates many times its original length and matures to form internode of the axis. The upper cell acts as nodal initial and the lower as internodal initial. The growth of the thallus is by dome-shaped apical cell which cuts off derivatives at its posterior surface Each derivative undergoes a transverse division to produce two daughter cells.
The reserve food material is starch and the cytoplasm show characteristic cyclic movement. The Cell wall of the internodal cell is impregnated with silica and calcium carbonate. There are many small ellipsoidal chloroplasts arranged longitudinally in peripheral portion of cytoplasm.
In the mature cells, the vacuole may be developed and may become multinucleated due to amitosis. Young cells are always uni-nucleated structures without conspicuous vacuole. They are usually two in number.Ĭortex: In some species, the intermodal cells is covered by a sheath of vertically elongated narrow cells, the cortex Such species are called as corticated. Stipuloids: These are unicellular out growth that arises from the basal node of each branchlet. The axillary branch continues the growth of thallus. They arise singly at the older nodes of the main axis. Long Branches: There are one or two branches of unlimited may also be present in each node. From each node arise the following four types of appendages,īranchlets: Each node bears a whorl of branches, which has limited growth. The axis is differentiated into node and internodes. The thallus has long slender upright branches. The erect, branched attached the substratum by means of rhizoids. The plant body or structure of charais as follow Thallus
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