Women have sex chromosomes xx, and men have sex chromosomes xy. which of a woman's grandparents could not be the source of any of the genes on either of her x chromosomes?

mother's father

father's mother

mother's mother

father's father

Red blood cells are responsible for transporting oxygen in the blood. people with sickle cell anemia were born with a defective gene that results in sickle-shaped red blood cells. individuals with the disease often suffer pain in their extremities due to the build-up of these cells causing blockages in the blood vessels. the shape of the blood cells also reduces the amount of oxygen transported in the blood.