For more on the meaning of colors for the color red. Orange is the color of social communication and optimism. From a negative color meaning it is also a sign of pessimism and superficiality. For more on the color orange. With the meaning of colors, in color psychology, yellow is the color of the mind and the intellect. It is optimistic and cheerful. However it can also suggest impatience, criticism and cowardice. For more on the color yellow.
The blood has several types of white blood cells including neutrophils, bands, eosinophils, basophils, monocytes and lymphocytes. Each fights infection in a different way. Neutrophils, for example, are one of the body's main defenses against bacteria. Neutrophils kill bacteria by ingesting them. Neutrophils can ingest five to 20 bacteria in their lifetime. Another type of white blood cell is called bands. Bands are immature neutrophils.
White blood cell: One of the cells the body makes to help fight infections. There are several types of white blood cells (leukocytes). The two most common types are the lymphocytes and neutrophils (also called polymorphonuclear leukocytes, PMNs, or polys).