genetic code

the instructions in genes that “tell” the cell how to make specific proteins. The code resides in the sequence of bases occurring as constituents of the genetic material, DNA or RNA. These bases are represented by the letters A, T, G, and C (which stand for adenine, thymine, guanine, and cytosine, respectively). In messenger RNA, uracil (U) replaces thymine. Each unit, or codon, of the code consists of three consecutive bases. Hence, there are 64 possible triplet combinations of the four bases, which specify the amino acids that make up each protein molecule.

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Psychology term of the day

December 22nd 2024

multistore model of memory

any theory hypothesizing that information can move through and be retained in any of several memory storage systems, usually of a short-term and a long-term variety. The first to propose a multistore model were U.S. cognitive psychologists Richard C. Atkinson and Richard M. Shiffrin (1942– ) in 1968 (see information-processing model), with other researchers subsequently proposing their own such models as well. Also called storage-and-transfer model of memory. See dual-store model of memory; modal model of memory.