Blood Basics
'Think of your blood as the transportation system in your body that's always on the move, making deliveries and pick-ups day and night. Pumped by your heart, your blood is circulated non-stop, carrying oxygen and nutrients to wherever they're needed, and collecting waste products called carbon dioxide."-Rory, from My Blood, Your Blood

Produced in the Bone Marrow, blood is comprised mainly of Red Blood Cells, White Blood Cells, Platelets, and Plasma. What are these, what are their function and why do we need them to save lives?
Red Blood Cells:
One of the cells of the blood, which, in mammals,are non-nucleated disks concave on both sides. The most numerous cell in the blood, Red Blood Cells are produced at a rate of 4-5 billion every hour. Red Blood Cells live for 120 days in the blood stream, but only 42 days outside of the body. When they die and are removed from circulation by an organ called the spleen.

Red Blood Cells contain hemoglobin (otherwise known as iron) and serve to transport oxygen through the bloodstream, to the tissues, and to the organs. After they deliver the oxygen, the red blood cells pick up a waste product called carbon dioxide, known as CO2. Then they make the return trip back to the lungs through the veins where the CO2 can finally be released. Every time you breathe out, you are ridding your body of Carbon Dioxide and waste. It takes, on average only 30-45 seconds for blood cells to make one complete circuit.
Used for? Severe Anemia to build the hematocrit level (iron) in the patient's blood. Accident victims, trauma patients, and surgeries to replace volume and the Red Blood Cells lost.
Plasma:
All of the blood cells in your body are mixed together in a slightly yellowish liquid called Plasma. Plasma is mostly made up of water, but also contains proteins, sugar and salt. In addition to carrying blood cells throughout your body, plasma also carries hormones, nutrients and chemicals, such as iron. Plasma has the important function of maintaining the pH of the blood.
Used for? Be used in conjunction with other blood components to build blood volume. Immune Deficiencies. Lubricate heart pumps and other machines that would be connected to the body. Burn victims need this component to replenish fluid and nutrients.
Platelets:
Your first defense. Platelets are sticky little guys that help prevent bleeding and make your blood clot when your cut. Formed from the largest of the stem cells, the Megakaryocyte , Platelets are the tiny fragments of cell material, better known as cytoplasm. Platelets are normally round and smooth, but after they are used to produce clots, they turn spiky and jagged around the edges. After an injury occurs, the Platelets throw themselves over the cut. From there, they spin a web called fibrin, that interlocks them and forms the scab. The platelets also attract a protein found in plasma called fibrin and use it to form a dense netting that traps red blood cells and quickly becomes a clot.

Used for? Hemophiliacs who have a platelet function abnormality. Chemotherapy patients to help them mend during the radiation. Given to accident victims to stop bleeding.
White Blood Cells:
The scientific name for white blood cells is Leukocytes. White Blood Cells are colorless cells of the immune system that circulate mainly in the blood and lymph. White blood cells are an important part of your body's immune system. Their role is to defend your body against infection by germs. There are many different kinds of white blood cells and each one has a very specific job to do. There are lymphocyte T cells and lymphocyte B cells, monocytes, and granulocytes. When the antibody weapon finds its target, the germ is stunned, wounded and killed.
Find out more about the history of blood, the biology of blood and how science is progressing in this field, go to 
