Ba's hydrops fetalis is lethal because -
Hb Ba's cannot bind oxygen
The excess a - globin form insoluble precipitates
Hb Ba's cannot release oxygen to fetal tissues
Microcytic red cells become trapped in the placental
Ans. is 'c' i.e., Hb Ba's cannot release oxygen to fetal tissues `In the foetus excess gamma globin chains form tetramers (Hb Bas) with such high affinity for oxygen that they deliver almost no oxygen to tissues' - Robbins o Clinically this condition manifests as hydrops fetalis and fetus shows features similar to those of erythroblastosis fetalis ----> Severe pallor, Generalized edema, Massive hepatosplenomegaly