CBSE Class 10 Science 2020 · Paper 31/3/3 · Question 28(b)

(a) Diagram: Rhizopus growing on moist bread, with thread-like hyphae spreading over the surface, rhizoids growing down into the bread, and upright hyphae (sporangiophores), each ending in a round sporangium full of spores; one sporangium is shown bursting and releasing its spores. Labels: sporangium, spores, sporangiophore (upright hypha), stolon (spreading hypha) and rhizoids. (b) Budding: a bud forms as an outgrowth at one specific site on the parent, grows into a tiny individual and detaches from the parent, which remains whole; for example, Hydra (or yeast). Fragmentation: a mature organism simply breaks up into two or more pieces (fragments), each of which grows into a new individual; for example, Spirogyra. (c) Vegetative propagation is used to grow plants that do not produce seeds, having lost the capacity to do so, such as banana, orange, rose and jasmine. It also gives plants that bear flowers and fruits earlier than plants raised from seeds, and all of them are genetically similar to the parent plant, so its desirable characteristics are kept.