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  1. Il y a 2 jours · DNA, organic chemical of complex molecular structure found in all prokaryotic and eukaryotic cells. It codes genetic information for the transmission of inherited traits. The structure of DNA was described in 1953, leading to further understanding of DNA replication and hereditary control of cellular activities.

  2. Il y a 4 jours · Molecular Biology is the field of biology that studies the composition, structure and interactions of cellular molecules such as nucleic acids and proteins that carry out the biological...

  3. Il y a 3 jours · Definition. A cell is the basic building block of living things. All cells can be sorted into one of two groups: eukaryotes and prokaryotes. A eukaryote has a nucleus and membrane-bound organelles, while a prokaryote does not.

  4. Il y a 3 jours · RNA, complex compound of high molecular weight that functions in cellular protein synthesis and replaces DNA as a carrier of genetic codes in some viruses. RNA consists of ribose nucleotides and the nitrogenous bases adenine, guanine, cytosine, and uracil.

  5. Il y a 4 jours · Ribonucleic acid (abbreviated RNA) is a nucleic acid present in all living cells that has structural similarities to DNA. Unlike DNA, however, RNA is most often single-stranded. An RNA molecule has a backbone made of alternating phosphate groups and the sugar ribose, rather than the deoxyribose found in DNA.

  6. Il y a 4 jours · An organelle is a subcellular structure that has one or more specific jobs to perform in the cell, much like an organ does in the body. Among the more important cell organelles are the nuclei, which store genetic information; mitochondria, which produce chemical energy; and ribosomes, which assemble proteins.