Describe how the various supportive tissues in plants adapt them to their habitats.(20m)

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-Sclerenchyma  tissue;  long,  slender  cells  with  tapering  ends;  with  walls  thickened  with  lignin; provide  support  and  protection  to  the  more  delicate  tissues;  and  resistance  to  storms  and  strong winds;  main  constituent  of  wood;
- Xylem  vessels;  longitudinally-elongated  cells;  with perforated  end  walls;  with  heavily  lignified  walls;  to  increase  rigidity  and  strength  to  the  plant; a  main  constituent  of  wood;
- Tracheids;  mainly  found  in  angiosperms;  made  up  of  long  tapering dead  cells;  cell  walls  are  highly  lignified;  and  pitted;  cells  lie  in  large  overlapping  groups;  to offer  extra  support;
- Collenchyma  tissue;  longitudinally  elongated  living  cells;  located  beneath the  epidermis  and  mid  rib  of  leaf  veins;  thickened  at  the  corners  by  cellulose  and  pectin compounds;  to  provide  support  in  leaves,  herbaceous  plants  and  young  woody  plants;
- Parenchyma  tissue;  large;  spherical  cells;  with  thin  cellulose  walls;  forming  the  bulk  of  cortex and  pith  of  most  plants;  become  tightly  packed  and  rigid  when  turgid;  to  attain  and  maintain  an erect  posture  of  plants;  main  support  structures  in  herbaceous  stems/plants;  Max.  20  mks 

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