Question

Blood from the foetus circulates through the placenta. What substances pass

i) from the maternal to the foetal blood

ii) from the foetal to the maternal blood

Answer 1

Blood from the foetus circulates through the placenta. The substances pass

i) from the maternal to the foetal blood - All the nutrients and oxygen to be used by foetus

ii) from the foetal to the maternal blood - All the waste products including nitrogenous waste and carbon dioxide, so that it can be eliminated from foetus via the body of mother.