People with O+ blood cannot donate their blood to negative blood types, while people with O- blood can donate to any blood type. This makes them the "universal donor." However, they can only receive O- blood.
Peristalsis is a series of wave-like muscle contractions that move food through the digestive tract. It starts in the esophagus where strong wave-like motions of the smooth muscle move balls of swallowed food to the stomach.
Phenotype; The expression of a particular trait, for example, skin color, height, behavior, etc., according to the individual's genetic makeup and environment.
