In adults,erythropoiesis occurs in

Blood examination of an anemic person reveals large,immature,nucleated erythrocytes without hemoglobin. Which of the following,if added to their diet,would alleviate the symptoms?

$A$ person with an unknown blood group under the $ABO$ system has suffered significant blood loss in an accident and requires an immediate blood transfusion. His friend,who has a valid certificate of his own blood type,offers to donate blood without delay. What would be the blood group of the donor friend?

The problem due to $Rh$ factor arises when the blood of two individuals ($Rh^+$ and $Rh^-$) mix up in which of the following conditions?

Who was the scientist to introduce $ABO$ blood groups?

Serum differs from blood in