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www.GOALias.blogspot.comNew plantFig. 12.4 Leaf of bryophyllum with buds in themarginThe roots of some plants can alsogive rise to new plants. Sweet potato anddahlia are examples.Plants such as cacti produce newplants when their parts get detachedfrom the main plant body. Eachdetached part can grow into a newplant.Boojho wants to know ifthere is any advantage ofvegetative propagation.multiply every few hours if sufficientnutrients are made available to them.Remember that yeast is a single-celledorganism. Let us see how theyreproduce?Activity 12.3(To be demonstrated by the teacher)Take a piece of yeast cake or yeastpowder from a bakery or a chemist shop.Take a pinch of yeast and place it in acontainer with some water. Add aspoonful of sugar and shake to dissolveit. Keep it in the warm part of a room.After an hour, put a drop of this liquidon a glass slide and observe under amicroscope. What do you observe? Youmay see the formation of new yeast cells(Fig. 12.5).Yeast cellDeveloping budChain of budsNew budPlants produced by vegetativepropagation take less time to grow andbear flowers and fruits earlier than thoseproduced from seeds. The new plantsare exact copies of the parent plant, asthey are produced from a single parent.Later in this chapter you will learnthat plants produced by sexualreproduction have characters of both theparents. Plants produce seeds as a resultof sexual reproduction.BuddingYou have already learnt about the tinyorganisms like yeast can be seen onlyunder a microscope. These grow andFig. 12.5 Reproduction in yeast by buddingThe small bulb-like projectioncoming out from the yeast cell is calleda bud. The bud gradually grows andgets detached from the parent cell andforms a new yeast cell. The new yeastcell grows, matures and produces moreyeast cells. If this process continues, alarge number of yeast cells are producedin a short time.135REPRODUCTIONIN PLANTS135