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.
Components of blood Blood is the medium in which all the cells are carried to transport nutrients and oxygen to the cells of the body. Blood is made up of four components. These are red blood cells, white blood cells, platelets and plasma. Blood is made up of 55% plasma and 45% solids. Red blood cells 99% of red blood cells are red blood cells or erythrocytes. They are red in colour due to the prescience of a red coloured protein called haemoglobin.