Normoblast
Encyclopedia
An erythroblast is a type of red blood cell
which still retains a cell nucleus
. It is the immediate precursor of a normal erythrocyte
.
Cell (biology)
The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos....
which still retains a cell nucleus
Cell nucleus
In cell biology, the nucleus is a membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes. The genes within these...
. It is the immediate precursor of a normal erythrocyte
Red blood cell
Red blood cells are the most common type of blood cell and the vertebrate organism's principal means of delivering oxygen to the body tissues via the blood flow through the circulatory system...
.
Nomenclature
The term normoblast is sometimes used as a synonym for erythroblast, but at other times it is considered a subcategory. In the latter context, there are two types of erythroblasts:- "normoblasts" - develop as expected
- "megaloblastMegaloblastA megaloblast is an unusually large erythroblast that can be associated with pernicious anemia and folic acid deficiency . It is differentiated from a normoblast, which is a normally-sized erythroblast. This kind of anemia leads to macrocytes...
s" - unusually large erythroblasts that can be associated with pernicious anemiaPernicious anemiaPernicious anemia is one of many types of the larger family of megaloblastic anemias...
and folic acid deficiency (collectively called megaloblastic anemiaMegaloblastic anemiaMegaloblastic anemia is an anemia that results from inhibition of DNA synthesis in red blood cell production. When DNA synthesis is impaired, the cell cycle cannot progress from the G2 growth stage to the mitosis stage...
)
Development
There are four stages in the development of a normoblast.| Illustration | Description | Image >- |  |
>- | Basophilic normoblast | >- | Polychromatic normoblast (also polychromatophilic) | >- | Orthochromatic normoblast (also orthochromatophilic) |
