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.
The components of human blood are: Plasma. The liquid component of the blood in which the following blood cells are suspended: Red blood cells (erythrocytes). These carry oxygen from the lungs to the rest of the body. White blood cells (leukocytes).These help fight infections and aid in the immune process.he components of human blood are: Plasma. The liquid component of the blood in which the following blood cells are suspended: Red blood cells (erythrocytes). These carry oxygen from the lungs to the rest of the body. White blood cells (leukocytes).