What makes the blood look red?

In blood

In a certain road accident, patient with unknown blood group needs immediate blood transfusion. His one doctor friend at once offers his blood. What was the blood group of the donor ?

If mother has 'O' blood group, child also has 'O' group. What can be the blood group of father?

What makes lemon sour

What makes the molecular crystals solid at low temperature ?

What type of blood is carried by the pulmonary artery ?

A woman with blood 'O' has a child with blood group 'O'. She claims that a man with blood group 'A' as the father of her child. What would be the genotype of the father, if her claim is right