![]() ![]() From archesporial cell primary parietal cell forms anther wall and sporogenous cell forms sporogenous tissue.ġ.When microspores develop wall around it then it is known as pollen grain.Haploid (n) microspores separate from tetrad.Microsporangium contains microspore mother cells (2n) which undergo meiosis to form microspore tetrad.Outer epidermis (Protective) followed by fibrous endothecium, thin walled middle layers and tapetum innermost nutritive layer. Anther wall is outer layer and microsporangium has sporogenous tissue.Mature anther has anther wall and microsporangium.Heterogeneity appears with formation of archesporial cell.Monothecous (Having single lobe) → Bisporangiate (Having two pollen sacs).Usually dithecous (Having two lobes) → tetrasporangiate (Having four pollen sacs).Gametes ← within flower ← Reduced structure ← gametophyte Diploid sporophyte is dominant plant body → Meiosis → Haploid spores → Sexual reproduction – Two major events –Ĩ. Flowers, specialized reproductive structure producing haploid gametes-ħ. Variations are useful for survival and evolution of species.Ħ. Production of genetically different offspring.ĥ. In higher plants, flowering indicates beginning of reproductive phase.Ĥ. Involves fusion of two compatible gametes (male and female).ģ. Micropropagation - Modern method to get plants from tissue culture.A small amount of plant tissue is carefully and aseptically grown to get plantlets.Joining of two plant parts stock and scion.New plants are identical to parent plant.Artificial methods useful in agriculture and horticulture.Reproduction with vegetative plant parts.Inheritance of genes of parent by progeny. Production of genetically identical progeny, i. Fusion of two compatible gametes or sex cell is not involved.Ģ. TWo types – Asexual reproduction and Sexual reproduction.ġ. ![]()
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