Oxygen Binding Of Single Red Blood-Cells Of The Annelid Bloodworm Glycera-Dibranchiata

The red blood cells of the annelid bloodworm Glycera dibranchiata contain two structurally and functionally distinct assemblages of hemoglobin. In the present sample the monomer comprised 57% and the polymer 43% of the total amount. The O2 affinities of the two differ by a factor of about two. Therefore, if the two assemblages occur in different cells, one would expect a bimodal distribution of P50 values for single RBCs and, if they coexist in the same cell, one would expect a monomodal distribution. The distribution is clearly monomodal, indicating no anatomical separation of mono- and polymeric hemoglobins.