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www.GOALias.blogspot.comFragmentationYou might have seen slimy greenpatches in ponds, or in other stagnantwater bodies. These are the algae. Whenwater and nutrients are available algaegrow and multiply rapidly byfragmentation. An alga breaks up intotwo or more fragments. These fragmentsor pieces grow into new individuals(Fig. 12.6). This process continues andthey cover a large area in a short periodof time.SoriFig. 12.8 Reproduction through spore formationin fernFig. 12.6 Fragmentation in spirogyra (an alga)Spore formationIn Chapter 1 you learnt that the fungion a bread piece grow from spores whichare present in the air. Repeat Activity1.2. Observe the spores in the cotton-HyphaSporangiumSporesFig. 12.7 Reproduction through spore formationin funguslike mesh on the bread. When sporesare released they keep floating in theair. As they are very light they can coverlong distances.The spores are asexual reproductivebodies. Each spore is covered by ahard protective coat to withstandunfavourable conditions such as hightemperature and low humidity. Sothey can survive for a long time. Underfavourable conditions, a sporegerminates and develops into a newindividual. Plants such as moss andferns (Fig. 12.8) also reproduce bymeans of spores.12.2 SEXUALREPRODUCTIONYou have learnt earlier the structure ofa flower. You know that the flowers arethe reproductive parts of a plant. Thestamens are the male reproductive partand the pistil is the female reproductivepart (Fig. 12.9).136SCIENCE