▁larger ▁than ▁their ▁normal ▁volume . ▁The ▁normal ▁er yth ro cy te ▁volume ▁in ▁humans ▁is ▁about ▁ 8 0 ▁to ▁ 1 0 0 ▁fem tol it ers ▁( f L = ▁ 1 0 − 1 5 ▁L ). ▁In ▁metric ▁terms ▁the ▁size ▁is ▁given ▁in ▁equivalent ▁cub ic ▁mic rom eters ▁( 1 ▁ μ m 3 ▁= ▁ 1 ▁f L ). ▁The ▁condition ▁of ▁having ▁er yth ro cy tes ▁which ▁( on ▁average ) ▁are ▁too ▁large , ▁is ▁called ▁macro cy t osis . ▁In ▁contrast , ▁in ▁micro cy t ic ▁an emia , ▁the ▁er yth ro cy tes ▁are ▁smaller ▁than ▁normal . ▁ ▁In ▁a ▁macro cy t ic ▁an emia , ▁the ▁larger ▁red ▁cells ▁are ▁always ▁associated ▁with ▁ins u fficient ▁numbers ▁of ▁cells ▁and ▁often ▁also ▁ins u fficient ▁hem og lo bin ▁content ▁per ▁cell . ▁Both ▁of ▁these ▁factors ▁work ▁to ▁the ▁opposite ▁effect ▁of ▁larger ▁cell ▁size , ▁to ▁finally ▁result ▁in ▁a ▁total ▁blood ▁hem og lo bin ▁concentration ▁that ▁is ▁less ▁than ▁normal ▁( i . e ., ▁an emia ). ▁ ▁Mac ro cy t ic ▁an emia ▁is ▁not ▁a ▁disease ▁in ▁the ▁sense ▁of ▁having ▁a ▁single ▁path ology ▁but , ▁rather , ▁is ▁a ▁condition . ▁As ▁such , ▁it ▁is ▁the ▁class ▁name ▁for ▁a ▁set ▁of ▁path ologies ▁that ▁all ▁produce ▁somewhat ▁the ▁same ▁red ▁blood ▁cell ▁ab normal ity . ▁D ifferent ▁path ologies ▁result