What is Blood Made of?

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What is in blood?

Blood is made of a liquid with several types of cells floating in it. The liquid part is called plasma and is mostly water, with chemicals in it.

Stem cells are parent cells made in the bone marrow. The stem cells make copies or clones of themselves. The cloned stem cells eventually become mature blood cells and are released into the blood stream. There are 3 basic types of blood cells: red blood cells, white blood cells and platelets.

Red blood cells are filled with hemoglobin, a protein that takes oxygen from our lungs and delivers it to the tissues and organs in our body. Too few red blood cells create anemia.

Platelets or thrombocytes are small pieces of cells that help your blood to clot and stop bleeding. Too few platelets is called thrombocytopenia.

White blood cells or leucocytes fight disease and infection by attacking and killing germs that get into the body. There are several kinds of which blood cells, each of which fights a different kind of germ. Too few white blood cells is called leucopenia.


What are Granulocytes?

Most white blood cells are granulocytes, so named because they have granules that show different colors when stained for microscopic examination. Neutrophils (cells that are neutral or those whose granules don’t pick up a stain) are normally the most common white blood cell in healthy folks.

Too few neutrophils (neutropenia) can be the result of chemotherapy and increase infection risks.


What are Lymphocytes?

Lymphocytes have no granules when examined under the microscope. There are three basic types of lymphocytes and many subtypes.

The first two, NK or natural killers and T cells are different parts of our cell-mediated or cellular immune response to threats from infections and cancers.

Chronic lymphocytic leukemia (CLL) always arises from the third type, the B cells.

These B-lymphocytes mature to make the antibodies that float in the liquid blood and so are said to be part of the liquid or humoral immune system. When you have CLL, too many cells turn into abnormal lymphocytes. These cells do not function properly — they do not fight infections efficiently and they do not die when they are supposed to, so the number of lymphocytes increases. Too many lymphocytes is called lymphocytosis.