What Does DNA Do?
DNA is responsible for almost everything that happens on a cellular level. DNA is the instructions that enable cells to carry out specific functions. Think of DNA as a blueprint for cellular activity. Below, we will explain the basic building blocks of DNA and how they relate to genes.
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There are four possible bases for DNA, they are Adenine, Thymine, Cytosine, and Guanine. In DNA, Adenine pairs with Thymine, and Cytosine pairs with Guanine. This is known as base pairing.
Nucleotides bond to form long chains, or strands, of DNA. The four bases can bond in any order, therefore many possible combinations of strands of DNA are possible. DNA is a double stranded molecule, with two strands of DNA bonding together and twisting. The structure of DNA is called a double helix. |
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So What Are Genes?
Well actually, Genes and DNA are somewhat synonymous. "Genes" are simply another name for the instructions that the long strands of DNA contain. Physically, a "gene" is just a section of a strand of DNA that codes for a function. Within one strand of DNA, there might be a single gene or multiple genes. Each gene codes for a specific function.
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Nucleotides are building blocks of DNA. Segments of the long strands of DNA code for different biological functions or characteristics. Long strands of DNA are wound into structures called chromosomes,
The information provided on this page holds true for the DNA structure of most animals. However, as one explores deeper into biology, it isn't uncommon to see organisms whose entire genetic code is stored on a ring of DNA, a single strand of DNA, or a strand of RNA (which we will get to later). Bacteria possess circular pieces of DNA called plasmids, and viruses have many different ways of storing their genetic information.