When model organisms cannot provide the information needed to answer a particular research question, biologists can turn to cultured human cells.
When model organisms cannot provide the information needed to answer a particular research question, biologists can turn to cultured human cells – which are grown in Petri dishes, in the same way as bacteria. Since cultured cells carry out all basic biochemical functions, they are often used to model specific tissue functions and diseases. Primary cells are derived directly from living tissue – such as blood, muscle, or nerve – and can only be cultured outside the body for a limited number of cell divisions. Immortalized cells have acquired mutations that free them from a fixed life span and allow them to divide indefinitely in culture. Cultured human cells have been especially important in studying the genetic and biochemical events that convert a normal cell into a cancerous one.Embryonic stem cells have the ability to become any cell type, and therefore have enormous potential in terms of replacing damaged cells in the humans body.