Final answer:
Cells sharing an identical genome means they have the same genetic instructions, yet only express a subset of genes, which allows for cell specialization. Genetic expression is regulated, enabling different cell types to develop within the same organism. Genomic variation within species is key to evolution.
Step-by-step explanation:
All cells of an organism sharing an identical genome means they have the same set of genetic instructions. Despite this shared genetic blueprint, individual cells express only a subset of their genes, allowing for cell differentiation. This concept is crucial for understanding how cells become specialized, such as skin cells or muscle cells, within the same organism. Genetic expression is regulated, and certain genes are turned on or off to produce the required set of proteins for a specific cell function.
The genomic variation within species is a cornerstone for evolutionary processes. Genome sequencing has illustrated not only the genetic differences between species but also the genetic diversity within a species. In the differentiation process, cells alter their gene expression, thereby leading to various cell types with distinct structures and functions, despite having the identical genome.