biology of blood

DEFINITION

Blood is a combination of fluid, cells and cell-like particles, which flow in the arteries, capillaries and veins; that deliver oxygen and nutrients to the tissues and carrying carbon dioxide and other waste results.

FLUID COMPONENTS.

More than half a fluid part of blood (plasma), most of which contain dissolved salts and proteins. Major protein in plasma is albumin. Other proteins are antibodies (immunoglobulins) and clotting proteins.
Plasma also contains hormones, electrolytes, fat, sugar, minerals and vitamins.

In addition to distributing blood cells, plasma also:- A reserve of water for the body- Prevent the wrinkle and the blocked blood vessel- Helps maintain blood pressure and circulation throughout the body.Even more importantly, antibodies in the plasma protects the body against foreign substances (such as viruses, bacteria, fungi and cancer cells), when the clotting proteins to control bleeding.

In addition to channel and regulate hormone effects, the plasma also cools and warms the body as needed.

COMPONENT SEL.

1.       Red blood cells (erythrocytes).

Cell is the most compared with two other cells, under normal

2.      Circumstances nearly half of the blood volume.  Red blood cells

contain hemoglobin, which allows red blood cells carry oxygen from the lungs and deliver it to tissues throughout the body.

3.     Oxygen is used to form the energy for the cells, with the waste material in the form of carbon dioxide, which will be transported by red blood cells from the tissue and returned to the lungs.

4.     White blood cells (leukosit.

Fewer in number, with a ratio of about one white blood cell for every 660 red blood cells.

There are five main types of white blood cells that work together to build the main mechanism of the body against infections, including producing antibodies.

 - Neutrophils, also called granulocytes because they contain enzymes that contain granules, amount at most.

  -Neutrophils help protect the body against bacterial and fungal infections and digest foreign matter remaining inflammation.

There are two types of neutrophils, which is ribbon-shaped neutrophils (immature, immature) and segmented neutrophils (mature, mature).

  - Lymphocytes have two main types, namely T lymphocytes (providing protection against viral infections and can find and destroy some cancer cells) and B lymphocytes (cells forming antibodies or cells that produce plasma).

 - Monocytes to digest the cells that die or are damaged and giving immunologic resistance against various infectious organisms.

 - Eosinophils kill parasites, destroy cancer cells and plays a role in the allergic response.

-         Basophils also play a role in the allergic response.

-          Platelets (thrombocytes).

-         Is paritikel that resembles the cell, with a size smaller than red blood cells or white blood cells.

-          As part of the protection mechanisms of blood to stop bleeding, platelets gather Dapa area experiencing bleeding and experiencing pengaktivan.

-         After experiencing pengaktivan, platelets will stick to each other and clumping together to form a blockage that helps close the blood vessels and stop bleeding.

-         At the same time, platelets release the materials that help facilitate clotting.

Red blood cells tend to flow smoothly in the blood vessels, but is not the case with white blood cells.Many white blood cells stick to blood vessel walls, or even through walls to get into another network.

If the white blood cells to areas that have an infection or other problems, they release substances that will attract more white blood cells.The function of white blood cells are like soldiers, spread throughout the body, but is ready to be collected and against the various organisms that enter the body.

BLOOD CELL FORMATION

Red blood cells, white blood cells and platelets made in the bone marrow.In addition, lymphocytes are also made in the lymph nodes and spleen; and T lymphocytes are made and matured in the thymus (a small gland near the heart).Thymus gland is active only in children and young adults.

In the bone marrow, all blood cells originate from a single type of cells called stem cells.If a stem cell divides, which was first formed red blood cells are immature (immature), white blood cells or cells that form platelets (megakariosit).Then if immature cells divide, will be mature and eventually become red blood cells, white blood cells or platelets.

The speed of blood cell formation is controlled in accordance with the needs of the body.If the content of oxygen in body tissues or red blood cell count decreases, the kidneys produce and release erythropoietin (a hormone that stimulates bone marrow to create more red blood cells).Bone marrow forms and releases more white blood cells in response to infection and more platelets in response to hemorrhage.

LABORATORY EXAMINATION FOR BLOOD

Doctors depend on a variety of different laboratory tests of blood samples to diagnose and monitor diseases.Some components and functions of the examination to measure the blood itself, other tests to assess the materials in the blood to determine the function of other organs.

Blood tests are most often performed complete blood counts (CBC, complete blood cell count), which is a basic assessment of blood cell components.A machine automatically performs these checks in less than a minute against a drop of blood.

In addition to determining the number of blood cells and platelets, the percentage of each type of white blood cell and hemoglobin content; blood cell counts are usually assess the size and shape of red blood cells.Abnormal red blood cells may break or shaped like a teardrop, a crescent or a needle.

By knowing the shape or size of the abnormal red blood cells, can help diagnose a disease.As an example of a crescent-shaped cells is typical for sickle cell disease, red blood cells are small can be a sign of early stages of iron deficiency and oval-shaped red blood cells showed a large deficiency of folic acid or vitamin B12 deficiency (pernicious anemia).

Other tests provide additional information about the blood cells.Reticulocyte count is the number of young red blood cells (reticulocytes) in a certain blood volume.Under normal circumstances, the number of reticulocytes reaching about 1% of the total number of red blood cells.

If the body requires more red blood (as occurs in anemia), bone marrow normally will provide more answers by forming reticulocytes.Because it is the rating of the reticulocyte count bone marrow function.

Examination that determines the characteristics of fragility and red blood cell membranes, help in assessing the cause of anemia.

White blood cells can be counted as a group (white blood cell count).If required a more detailed description, can be done calculating certain types of white blood cells (white blood cell differential count).

Platelets can also be calculated separately.

One of the most frequent examinations were performed on plasma electrolyte analysis.Performed measurements of sodium, chloride, potassium and bicarbonate, calcium, magnesium and phosphate.

Other tests measure the amount of protein (usually albumin), sugar (glucose) and toxic waste materials that are normally filtered by the kidneys (kretinin and blood urea-nitrogen).

Most other blood tests help monitor the function of other organs.Because blood brings many materials that are essential for body functions, blood tests can be used to find out what happens in the body.In addition, blood tests are relatively easy to do.Eg thyroid function can be more easily assessed by measuring levels of thyroid hormones in the blood compared to directly take the example of the thyroid.Similarly, the measurement of liver enzymes and proteins in the blood is more easily done than by taking the example of the liver.

Bone marrow examination

Sometimes the bone marrow samples must be examined to determine the cause of abnormal blood cells.Examples of the bone marrow can be obtained through two ways, namely through bone marrow aspiration or biopsy of bone marrow center.

Both ways are usually taken from the bones of the pelvis (iliac crest), although sometimes aspiration is taken from the breastbone (sternum).In small children, taken from the backbone (vertebrae) or lower leg bone (tibia>).

Both types of samples are usually taken at the same time.Having given a local anesthetic to the skin and tissue over the bone, put a needle into the bone.

On samples of bone marrow has been sucked through the needle, can be a special examination, such as culturing bacteria, fungi or viruses and chromosome analysis.

Although the results of aspiration can provide enough information to determine a diagnosis, but the process of withdrawal of the bone marrow into the syringe can damage the fragile bone marrow.Consequently it is difficult to determine the original composition of blood cells.

If the exact anatomical relationship of the cells must be determined and the structure of the network should be assessed, then the center of the bone marrow biopsy.A small portion of an intact bone marrow removed with a special tool on a needle.This section is then cured and cut into thin and then examined under a microscope.

Sampling of bone marrow usually causes only mild pain and little discomfort.The procedure only takes a few minutes.

Source : http://medicastore.com/penyakit/160/Biologi_Darah.html