Erythropoiesis. The process through which new red blood cells are created; it begins in the bone marrow. Mentioned in: Porphyrias. the formation of red blood cells (erythrocytes) from stem cells in the bone marrow.
2 Unicelluar organisms are one-celled organisms or microorganisms. Although they are living things that are only one cell, they still need to carry out all 6 characteristics of life. For example, they must feed, digest, excrete wastes and reproduce. They are very small and surround you every day by the millions.
These one celled, or unicellular, organisms (including bacteria, plants, fungi and animals) have the same characteristics of living things that you have! It is simply amazing that a simple one celled organism can do all the basic life functions you can do!...... But wait a minute, let's put this in perspective....