* DNA contains the genetic code: DNA holds the instructions for building and maintaining an organism. These instructions are encoded in the sequence of its four nucleotide bases (A, T, C, G).
* Genes code for proteins: Specific segments of DNA called genes contain the blueprint for creating proteins.
* Enzymes are proteins: Most enzymes are proteins, and some are made of RNA (ribonucleic acid).
* Transcription and translation:
* Transcription: The DNA sequence of a gene is copied into a messenger RNA (mRNA) molecule.
* Translation: The mRNA molecule travels to ribosomes, where the genetic code is read, and amino acids are linked together to form a protein.
* Protein folding: The newly formed protein chain then folds into a specific three-dimensional shape, which is essential for its function.
Therefore, the DNA sequence of a gene determines the amino acid sequence of the protein, which in turn determines the enzyme's structure and ultimately its function.
Here's a simplified analogy:
Imagine DNA as a cookbook. Genes are individual recipes. The recipes tell you what ingredients (amino acids) and the order they should be combined (protein sequence) to create a dish (enzyme). Following the recipe carefully ensures you end up with the intended dish.
