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Knowledge and Skills Statement

Science concepts--mechanisms of genetics. The student knows the role of nucleic acid in gene expression.

a polynucleotide (nucleic acid) found in most organisms as the genetic material; composed of a specific combination of monomers of nucleic acid, the combination of which determines the genetic sequence of organisms; made up of a sugar (deoxyribose), a phosphate, and a nucleic acid (one of Adenosine, Thiamine, Guanine, and Cytosine)

describes how certain proteins are manufactured according to a recipe found within the DNA; the mechanism by which certain genes are turned on, up, down, or off, resulting in variations in the amount of product they produce

long-chain polymeric biomolecule; main information-carrying molecule of the cell; determines the inherited characteristics of every living thing

an organic molecule that is the building block of DNA and RNA; composed of a five-carbon sugar (ribose or deoxyribose), a phosphate group, and one of five nitrogenous bases (cytosine, adenine, thymine, guanine, or uracil)

specific variations in the features of organisms received from a parent or ancestor by genetic transmission

Research

Forterre, Patrick, Jonathan Filée, and Hannu Myllykallio. “Origin and Evolution of DNA and DNA Replication Machineries.” In: Madame Curie Bioscience Database [Internet]. Austin (TX): Landes Bioscience; 2000-2013. Available from: https://www.ncbi.nlm.nih.gov/books/NBK6360/.
https://doi.org/10.1007/0-387-26887-1_10

Summary This article describes possible mechanisms for the transition from an RNA-dominant world to the current DNA-dominant one. Recent data have revealed that the multiple different enzymatic activities necessary for this transition have been invented independently, multiple times. Multiple hypotheses have been proposed to explain the current state, including the possible role of viruses in the origin of DNA replication and possibly of DNA itself.