fonalitÃ© | Flickr. American Express uses the first two numbers of the card to identify itself. That two-digit number will be either 34 or 37. The third and fourth digit signify the type of card and the currency being used, according to Clearpoint Credit Counseling.
Formed Elements of the Blood. the solid fraction of the blood, consisting of erythrocytes, leukocytes, and thrombocytes. The formed elements constitute up to 40 percent of the volume of the blood in lower vertebrates (fishes, amphibians, and reptiles) and up to 54 percent in higher vertebrates (birds and mammals, including man). The most numerous among the formed elements of the blood are the erythrocytes, which contain hemoglobin. They transfer oxygen from the respiratory organs to the tissues and help transfer carbon dioxide in the opposite direction.
Your blood is made of white blood cells, red blood cells,  platelets, and plasma.   The white blood cells fight infections and are part of the body's  immune system.aguely speaking, human blood is composed of blood cells, plasma, and platelets More specifically, Human blood has about 45% blood cells and 55 percent plasma. The blood cel â¦ ls contain erythrocytes(red blood cells) and leukocytes(white blood cells), but it's mostly red blood cells.