Eventually little or no telomere remains, and the cell dies. Any factor in the environment which can cause an abnormality in a developing embryo. A tumor composed of an unorganized collection of different tissues. Cells that have the ability to develop into any of the many different cell types which make up multicellular organisms. Embryos are composed of large numbers of totipotent cells which decline in number as development proceeds and cell specialization begins to occur.
Adults have a much more limited ability to produce totipotent cells than do embryos.
Organisms such as humans retain a complete set of genetic information in all adult body cells yet only a small fraction of an adult's cells have the ability to develop into multiple cell types. Recent research has shown that differentiated adult cells can be treated such that they become totipotent. Currently, the premier toxicogenomic tools are the DNA microarray and the DNA chip, which are used for the simultaneous monitoring of expression levels of hundreds to thousands of genes. Compare translation . RNA molecules which bond with amino acids and transfer them to ribosomes , where protein synthesis is completed.