Provide an example of why it is advantageous for a cell to control gene expression?

Answer 1

I can see a few advantages for the cell to control gene expression.

The first is to allow cell differentiation from a communal cell progenitor, through the expression of markers of differentiations (which are proteins, most often expressed on the cell membrane). A good example of this process is the differentiation of blood cells into all the needed sorts (white cells, i.e. leukocytes, macrophages, megakaryocytes, etc; red cells, etc).

A second advantage is that of saving energy when the product of a certain gene is not required. The gene is only switched on when the organism needs that specific protein. Insulin and glucagon (as well as all other hormones) are good examples for this mechanism.

Finally, the regulation of genes in cell cycle allow the progression of the latter. In order for the cell to divide, the expression and activation of sequential complexes in needed and the order has to be maintained, or the cell cycle progression is compromised (I am thinking of CDK/Cyclin complexes, mostly): first the CDK4/Cyclin D complex is activated, then the CDK2/Cyclin E and CDK2/Cyclin A, much later CDK1/Cyclin B. Cyclins are only expressed when needed in the cell cycle, that´s why they are called cyclins.

In one word: it is all about saving energy for the cell.
Hope this help

Answer 2

the cell has to work less =]]]]]]]]
poop