Red blood cells (RBCs) are a type of blood cell whose role is to transport oxygen from the lungs to the peripheral tissues of the body. Oxygen diffuses from the alveoli of the lungs into the RBCs, where it binds to hemoglobin. One molecule of hemoglobin can bind four molecules of oxygen (O2).
Because there is insufficient evidence to support the idea that all chimpanzees use tools. the scientist would need lots of hard evidence supporting this conclusion (lots of chimpanzees using tools)
