Reading: Sickle cell disease is a disorder that affects the red blood cells, which use a protein called hemoglobin to transport oxygen from the lungs to the rest of the body. Normal red blood cells are round and flexible so they can travel freely through the narrow blood vessels and carry oxygen around the body. Patients with sickle cell disease have a mutation in a gene on chromosome 11 that codes for the hemoglobin protein. As a result, hemoglobin molecules don't form properly, causing red blood cells to be rigid and have a concave shape (like a sickle used to cut wheat). These irregularly shaped cells get stuck in the blood vessels and are unable to transport oxygen effectively, causing pain and damage to the organs. Question #1: How does sickle-disease affect your red blood cells shape and function?