https://www.khanacademy.org/science/ap-biology/gene-expression-and-regulation/dna-and-rna-structure/v/dna-deoxyribonucleic-acid 2023-06-06T10:35:22.92767095Z DNA DNA, or deoxyribonucleic acid, is the molecular basis for inheritance, discovered in the mid-1800s and understood in 1953 with the double helix structure. Composed of a sugar-phosphate backbone and base pairs (adenine-thymine, guanine-cytosine), DNA stores genetic information, replicates, and expresses traits. The human genome contains 6 billion base pairs across 46 chromosomes, making it a compact and efficient information storage system. Sal Khan video https://cdn.kastatic.org/googleusercontent/N-FD1seHs-vdXACc6Ug4MuC44TkW3_s9SQcxTbnTpvAsX9wVNZXctud872V8KvhGq_fRRDQjDIVNX55fJrm1WiMGGw DNA DNA, or deoxyribonucleic acid, is the molecular basis for inheritance, discovered in the mid-1800s and understood in 1953 with the double helix structure. Composed of a sugar-phosphate backbone and base pairs (adenine-thymine, guanine-cytosine), DNA stores genetic information, replicates, and expresses traits. The human genome contains 6 billion base pairs across 46 chromosomes, making it a compact and efficient information storage system. https://cdn.kastatic.org/ka-youtube-converted/AmOO4j0E408.mp4/AmOO4j0E408.mp4 782 Structure of DNA https://www.khanacademy.org/science/hs-bio/x230b3ff252126bb6:gene-expression-and-regulation/x230b3ff252126bb6:dna-structure-and-replication/a/dna-structure 2026-03-18T10:10:31.931963487Z DNA structure Learn about complementary nucleotide base-pairing and antiparallel strands in the DNA double helix. article https://www.khanacademy.org/science/ms-biology/x0c5bb03129646fd6:inheritance-and-variation/x0c5bb03129646fd6:genes-proteins-and-traits/a/genes-proteins-and-traits-ms 2026-02-27T17:50:36.702607024Z Genes, proteins, and traits Learn about how genes encode proteins, which in turn affect an organism's traits. article https://www.khanacademy.org/science/revision-term-1-ka-biology-grade-11/x1474e0ca4285b2f5:week-3/x1474e0ca4285b2f5:biomolecules/e/dna-structure 2026-04-08T00:36:09.500768563Z DNA structure Questions to practice DNA structure Moumita exercise