What is DNA Structure?

DNA is a double-helix - it looks like a twisted ladder. Its backbone is made of sugars (deoxyribose) and phosphate groups, and the rungs of the ladder are made from 4 nitrogenous bases: Guanine, Adenine, Thymine, and Cytosine. The order of the “rungs,” or bases, is what determines what the DNA is coding for. Think of it like the order of letters in a word, and the order of words in a sentence. Except in the language of DNA, there are only 4 letters. In this video, we discuss the structure of DNA - how big is it, how are the components attached to each other, and what is the spacing between the rungs. We’ll also learn about the major groove and minor groove, and other important details about DNA structure.

Additional study materials
A short set of study notes about DNA structure.
DNA Structure - Study Notes
A short set of study notes about DNA structure.
A short set of study notes about DNA structure.
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Biology is the study of Life. In this course, we will explore topics in Biochemistry, Cell Biology, Genetics, Molecular Biology, Viruses, Evolution, Bacteria and Archaea, Protists, Plants (Botany), Fungi, Animals (Zoology), Anatomy & Physiology,Reproduction, Development, Animal Behavior, and Ecology. This course is designed for advanced High School Students (AP Biology) and first and second-year college students. Many topics in modern biology are dependent on an understanding of Chemistry - we encourage you to explore our Chemistry playlist as well!