Describe the process of gaseous exchange in terrestrial plants

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  Gaseous  exchange  occurs  in  the  spongy  mesophyll;  During  the  day,  air  diffuses  into  large  air spaces  of  the  spongy  mesophyll;  through  the  stomata;  the  carbon  (IV)  oxide  in  the  air  diffuses into  photosynthetic  cells;  in  solution  form;  during  photosynthesis,  carbon  (IV)  oxide  is  used up;  while  oxygen  is  produced;  some  of  the  oxygen  is  used  in  respiration;  while  the  rest  diffuses out  of  the  leaf;  through  the  stomata;  During  the  night,  air  diffuses  into  the  air  spaces;  through the  stomata;  the  air  dissolves  into  the  film  of  moisture;  oxygen  in  the  air  diffuses  into  the  cells; and  is  used  for  respiration;  carbon  (IV)  oxide  produced;  diffuses  out  through  stomata;  due  to  a concentration  gradient/diffusion  gradient;  At  night,  carbon  (IV)  oxide  accumulates  in  the  leaf since  photosynthesis  does  not  occur;  some  gaseous  exchange  also  takes  place  through  the cuticle;  and  through  the  epidermis  of  young  leaves,  roots  and  stems;  some  plants  exchange gases  through  breathing  roots/pneumatophores;  older  stems  exchange  gases  through  lenticels; Max 20  mks 

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