Transport of Glucose

I . The ra te of egress of glucose from h u m a n red b lood cells into saline med ia e i ther wi thou t sugar or conta in ing glucose, galactose, sorbose or fructose has been de t e rmined at 25 ° and for glucose or zero sugar at o °. 2. F r o m these da ta , using a simplified form of the theore t ica l analysis of RECEN AND MORGAN 18, i t is shown t h a t the ra te of movemen t across the m e m b r a n e of the s u b s t r a t e c a r r i e r complex is g rea te r t han t ha t of the free carrier , t h a t is, the movemen t of carr ier is fac i l i t a ted b y the subs t ra te . 3A lower l imi t of 2.8 is der ived for the ra t io of these ra tes of movement . 4. Evidence is p resen ted t ha t the aldoses and ketoses share a common carrier.