Deoxyribonucleic acid (DNA)
Definition
Deoxyribonucleic acid (DNA) is a molecule that contains the genetic instructions for building, operating, and maintaining all living organisms. It acts as the "blueprint" of life by storing information in a code made up of four chemical bases: adenine (A), thymine (T), cytosine (C), and guanine (G). These bases are arranged in a specific order along two twisting strands that form a double helix structure. DNA is found in nearly every cell in the human body and determines traits such as eye color, height, and susceptibility to certain diseases.
Example
Imagine you have a sibling who has curly hair while you have straight hair. This difference is due to variations in your DNA sequences. Your parents' DNA combines during fertilization, creating a unique genetic code for each child. The specific arrangement of A, T, C, and G in the DNA strands determines whether the hair follicle cells produce curly or straight hair.
Why it Matters
DNA matters because it defines who we are as individuals and connects us to all other living organisms on Earth. It determines our physical characteristics, influences our health, and plays a crucial role in evolution by allowing genetic information to be passed down through generations. Understanding DNA helps scientists develop medical treatments, improve agricultural practices, solve criminal cases using forensic science, and even trace our ancestry back thousands of years. Without DNA, life as we know it would not exist.