Describe what happens in a flower from the time of pollination up to the time of seed and fruit .

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development After  pollination,  the  pollen  grain  absorbs  nutrients  from  the  stigma;  and  develops  a  pollen tube;  it  grows  down  the  style  to  the  embryosac;  taking  along  the  male  nuclei;  the  tube  nuclei initiates  and  maintains  pollen  tube  growth;  while  the  generative  nucleus  divides  by  mitosis;  to form  two  male  gamete  nuclei;  which  follow  behind  the  tube  nucleus  as  the  pollen  tube  grows down  the  style;  pollen  tube  enters  the  ovule  through  the  micropyle;  its  tip  bursts  open;  while the  tube  nucleus  disintegrates;  one  of  the  male  gamete  nucleus  fuses  with  the  egg  cell nucleus/oosphere/megaspore;  to  form  the  zygote;  while  the  other  fuses  with  the  two  polar nuclei;  to  form  a  triploid  nucleus;  called  the  primary  endosperm  nucleus;  after  fertilization,  the zygote  undergoes  repeated  mitotic  divisions;  to  form  an  embryo  consisting  of  the  plumule, radicle  and  seed  leaves/cotyledons;  primary  endosperm  nucleus  divide  repeatedly,  become separated  by  membranes;  to  form  an  (semi-fluid  nutritive)  endosperm;  ovary  walls  change  into the  pericarp;  ovary  changes/develops  into  a  fruit;  while  ovules  lose  water  and  become  seeds; the  integuments;  change  into  seed  coats/testa;  style/filaments/petals/sepals  wither  and  fall  off (or  may  persist);  Max.  20  mks 

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