Double fertilization.
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   One sperm fertilizes the egg to form the zygote.
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   The  other  combines  with  two  polar  nuclei,  producing  a triploid
   endosperm, which serves as food supply.
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   Each  ovule  develops  into  a seed enclosed by a protective seed coat
   derived from the integument.
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   The ovary develops into a fruit enclosing the seed(s).
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   Thus a fruit is an organ containing one or more seeds.
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   Review:  <A ClAsS=MID Href="../../../med/Vid/double_fertilization.swf" oNClick="popurlt('../../../../med/Vid/double_fertilization.swf');txtcolor('double_fertilization1','gray');return false;" Id=double_fertilization1><iMg sRc="/images/shockwave.gif" aLt='' boRDer=0></A>
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