Here's why:
* DNA contains genes: DNA is a long molecule containing the genetic code, made up of sequences of nucleotides (A, T, C, and G). Specific segments of this code are called genes.
* Genes code for proteins: Each gene carries the instructions for building a specific protein. Proteins are the workhorses of the cell, carrying out a vast range of functions:
* Enzymes: Catalyze biochemical reactions.
* Structural components: Provide support and shape to cells.
* Signaling molecules: Communicate between cells.
* Transport proteins: Move molecules across cell membranes.
* Proteins determine cell function: The specific proteins produced by a cell dictate its functions. Different cell types (e.g., muscle cells, nerve cells, skin cells) express different sets of genes, leading to the production of different proteins and thus distinct functionalities.
Therefore, DNA, through the genes it contains, ultimately determines the proteins a cell produces, which in turn dictate its functions.
