Human Anatomy – Blood
- Human Anatomy – Tonsils
- Human Anatomy – Teeth
- Human Anatomy – Stomach
- Human Anatomy – Tongue
- Human Anatomy – Esophagus
- Human Anatomy – Liver
- Human Anatomy – Gallbladder
- Human Anatomy – Spleen
- Human Anatomy – Pancreas
- Human Anatomy – Appendix
- Human Anatomy – Intestines
- Human Anatomy – Colon
- Human Anatomy – Abdomen
- Human Anatomy – Penis
- Human Anatomy – Bladder
- Human Anatomy – Kidneys
- Human Anatomy – Prostate
- Human Anatomy – Vagina
- Human Anatomy – Heart
- Human Anatomy – Skin
- Human Anatomy – Aorta
- Human Anatomy – Thyroid
- Human Anatomy – Lungs
- Human Anatomy – Brain
- Human Anatomy – Eyes
- Human Anatomy – Ears
- Human Anatomy – Sinuses
- Human Anatomy – Trachea
- Human Anatomy – Blood
- Human Anatomy – Rotator Cuff
- Human Anatomy – Shoulder
- Human Anatomy – Feet
- Human Anatomy – Hair
- Human Anatomy – Achilles Tendon
Circulating throughout the body is the life-sustaining red liquid known only as blood. Oxygen and nutrients are ferried to all the cells in the body via the blood, which in turn carries away carbon dioxide and other waste materials. It also fights infections and helps regulate body temperature.
Because of the many proteins and materials it carries, blood is literally thicker than water. Blood is comprised of three kinds of cells, namely the red blood cells, white blood cells, and platelets. Red blood cells distribute oxygen around the body, while white blood cells defend the body against infections. The much-tinier platelets take charge of blood clotting.
Watering down blood is a fluid known as plasma, which takes up half of whole blood volume. Blood plasma is almost made up of water, but it also contains proteins with a variety of functions. It also holds dissolved nutrients such as glucose.
Blood cells are manufactured mostly in the marrow of certain bones, i.e. the spine (backbone), skull, sternum (breastbone), ribs, humerus, femur, and pelvis. Earlier in life, they are also produced in bone marrows elsewhere in the body. On average, a human being holds more than a gallon of blood.
Blood plies the entirety of the body through the blood vessels, otherwise called the veins and arteries. Their smooth lining prevents blood from clotting inside them.
Both veins and arteries wind up in the heart, the blood-pumping organ of the body. Blood already used by the body’s cells journeys towards the heart through the veins, while oxygenated blood ventures out of the heart via the arteries.
Blood diseases and conditions
Bleeding is known in medical parlance as hemorrhage. Many hemorrhages are external, such as those from wounds and cuts. Others are internal and not immediately visible from outside. Internal hemorrhages lead to hematoma or the accumulation of blood in the tissues.
Too less or too much of any blood cell in the blood is very risky. Too low levels of blood platelets cause thrombocytopenia, which in turn causes hemorrhage. An abnormally high number of red blood cells, a condition known as polycythemia, can cause difficulty breathing and an enlarged spleen.
In converse, anemia is when there are abnormally low levels of red blood cells. It almost always causes fatigue and trouble breathing. Hemolytic anemia happens after a substantial amount of red blood cells burst all at once.
Leukopenia is a condition of the blood wherein white blood cells drop to abnormally low numbers. It often occurs during an especially strong infection.
Leukopenia’s opposite is the blood cancer known only as leukemia. In this cancer, the number of white blood cells increases meteorically, the surfeit of which end up in tissues throughout the body. A similar type of blood cancer is called lymphoma, wherein white blood cells abnormally increase within the lymph nodes.
There is another blood cancer, which involves the cells of the plasma. Called multiple myeloma, this cancer may progress into kidney failure.
If not by their numbers, red blood cells can undermine the body by their shape alone. A hereditary condition called Sickle cell disease causes the red blood cells to appear sickle-shaped rather than as discs. These misshaped cells accumulate in tissues, leading to organ failure.
One of the world’s deadliest diseases also involves the red blood cells. When red blood cells become infected by mosquito-borne parasites called plasmodia, then malaria is on the move. Malaria progresses into organ damage.
If anything, blood should clot properly. If not, then catastrophic consequences result.
A person is said to be in a hypercoaguable state when he or she becomes very susceptible to blood clots. The clotting highly runs the risk of occurring in a coronary artery, setting up the person for a heart attack (myocardial infarction).
A clot occurring in a deep vein is highly likely to transfer to the lungs. This condition, called deep venous thrombosis, leads to pulmonary embolism.
Cancer and severe infections can cause a blood clotting condition called disseminated intravascular coagulation. During this condition, tiny blood vessels simultaneously undergo clotting and bleeding.
There are cases wherein people inherit a condition depriving them of some important proteins for blood clotting. This condition is called hemophilia, and it certainly leads to hemorrhages.
Too much iron in the blood, a condition known as hemochromatosis, may just be as problematic as any of the above. The excess iron frequently builds up in organs like the liver and pancreas. Diabetes is an offshoot of hemochromatosis.
Moreover, bacterial blood infections, e.g. bacteremia, are urgent conditions. Individuals whose bloods are infected with bacteria need intravenous infusions of antibiotics.
Treating blood conditions
Blood cancers, especially leukemia and lymphoma, require chemotherapy. Most doctors and healthy lifestyle experts recommend nothing less.
When sufficient enough, blood loss can be just as dangerous as the most life-threatening blood cancer around. Fortunately, any loss can be replaced with blood transfusion.
Another kind of transfusion is used by doctors to treat thrombocytopenia. Called platelet transfusion, it is done by collecting platelets from a donor and concentrating them in a plastic bag.
As for red blood cell deficiency, doctors take advantage of erythropoietin, a hormone naturally occurring in the kidney. Synthetic forms of the hormone are available in the market.
Blood clotting can be treated in several ways, foremost of which is taking anti-coagulating drugs like warfarin, heparin and enoxaparin. Anti-platelet medicines are also designed to prevent blood clotting. Common examples are aspirin and clopidogrel.
But if the body needs blood clots instead, a plasma transfusion becomes necessary. Plasma transfusion can replenish certain proteins used for blood clotting. One way to do plasma transfusion is by cryoprecipitation of certain proteins, i.e. collecting them from plasma and freezing them for storage.
Polycythemic patients are advised to undergo bloodletting, just to eliminate their surplus of red blood cells.
Tests for blood conditions
Many a healthy lifestyle tip encourage taking blood tests. These tests take several forms.
One is CBC or a complete blood count. It sizes up the number of all three kinds of blood cells in the body. Medical examiners have automated counters for CBCs.
Anemia, malaria, blood cancers, and other conditions are often diagnosed using blood smears. This is a blood test done by smearing drops of blood on a slide, which is then examined under a microscope.
Blood cultures are used to determine bacteria and other infectious presences in the blood. On the other hand, Coombs tests are used to search for antibodies responsible for depleting red blood cell levels, making them good tests for anemia.
If these blood tests are not able to pinpoint certain conditions, then a doctor may order a bone marrow biopsy. In this procedure, a medical examiner injects the hip bone with a needle, sucking out marrow for tests.
Prospective blood donors need to tell their blood type for doctors to determine their compatibility with the recipient. If the donor doesn’t know, he or she should undergo a blood type test. A medical examiner can determine one’s blood type, i.e. O, A, B, and AB, by looking at the antigens on red blood cells.