, ▁eat ▁tr uff les , ▁which ▁surv ived ▁under ground , ▁and ▁leave ▁f ec es ▁containing ▁nit ro gen - fix ing ▁b acter ia ▁in ▁the ▁soil . ▁Following ▁one ▁d orm ant ▁winter ▁stage , ▁the ▁seed ▁begins ▁to ▁germ inate . ▁ ▁In ▁the ▁second ▁chapter , ▁" T aking ▁Root ", ▁the ▁emb ry onic ▁root ▁emer ges ▁through ▁a ▁small ▁opening ▁in ▁the ▁seed ▁coat ▁and ▁through ▁cell ▁division , ▁a ided ▁by ▁plant ▁h orm ones , ▁it ▁grows ▁down ward . ▁Water ▁and ▁nut ri ents ▁enter ▁the ▁root ▁by ▁os mos is ▁and ▁are ▁transport ed ▁to ▁the ▁seed ling . ▁A ▁sym bi otic ▁relationship ▁develop s ▁between ▁the ▁roots ▁and ▁the ▁tr uff les . ▁The ▁roots ▁give ▁its ▁extra ▁sug ars ▁to ▁the ▁tr uff les , ▁which ▁it ▁uses ▁for ▁energy , ▁and ▁the ▁tr uff les ▁assist ▁the ▁roots ' ▁u pt ake ▁of ▁water ▁and ▁nut ri ents . ▁From ▁excess ▁st arch es ▁and ▁nut ri ents ▁gathered ▁by ▁the ▁root , ▁a ▁stem ▁similar ▁to ▁the ▁root ▁but ▁surrounded ▁with ▁thin , ▁gray ish ▁b ark , ▁grows ▁up wards . ▁As ▁the ▁st arch ▁res erves ▁are ▁exha usted , ▁its ▁first ▁need les ▁spr out ▁and ▁photos yn thesis ▁begins . ▁The ▁tree ▁anch ors ▁itself ▁with ▁a ▁deep ▁tap root ▁and ▁a ▁web ▁of ▁roots ▁begin ▁to ▁grow ▁later ally . ▁Some ▁roots ▁develop ▁sym bi otic ▁relationships ▁with ▁near - by