Q1. Why can twins resulting from a single fertilized egg exchange blood or receive organ transplants from each other without rejection, as twins resulting from two fertilized eggs sometimes cannot?
Q2. You have been injected into the femoral vein? What is the path from the right femoral vein to the lower lobe of the right lung? What is the path that I would take from the right femorla vein to the lower lobe of the right lung via right pulmonary artery?
Q3. Why do elderly people tend to develop cancer more often than younger people and how does this relate to the immune system?