Final answer:
Cell differentiation is the process where unspecialized cells become specialized, changing in function, size, shape, and metabolic activity. Cell types express different genes despite having the same genome, with transcription factors being crucial in gene regulation. Abnormal cell cycle regulation and differentiation can lead to cancer.
Step-by-step explanation:
Differentiation in the Cell Cycle
Cell differentiation is the process by which unspecialized cells, such as stem cells, become specialized into various cell types with unique structures and functions. During the development of an organism, cells progress through the cell cycle, which is an ordered series of events involving growth and division. However, part of the cycle's regulation involves signals that prompt certain cells to exit the cell cycle and specialize. This differentiation is critical for forming different tissues and organs.
Each cell type expresses only a portion of the genes contained in the organism's complete genome, much like actors reading only their parts from a movie script. Transcription factors play a key role in this selective gene expression, guiding cells into assuming specific roles within the body. When a cell differentiates, it may change in size, shape, metabolic activity, and function to meet the needs of its role.
Stem cells have the capacity to divide indefinitely and can differentiate into specialized cells under certain conditions. This differentiation process is vital for growth, repair, and maintenance of tissues. Aberrations in these signals or the inability to exit the cell cycle correctly can lead to uncontrolled cell growth, a hallmark of cancer.