What is the definition of polar molecule?

The picture showed normal blood cells which are around and sickle cells which appear much longer people with sickle-cell suffer from the sickle cell anemia which is inherited diseaseit is caused by a change in gene responsible for production of hemo goblin this type of change is known as an

Which structure in the cardiovascular system connect arteries to veins?

All other things being equal the size of a population will decrease if