Ba's hydrops fetalis is lethal because -
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
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