in proteins, certain specific orderings of secondary structure that may have a functional role and include Î²-Î±-Î² helix-turn-helix, leucine zippers, calcium binding EF hands, zinc fingers and longer orderings that take on a structural domain such as the Î²-barrel and the immunoglobulin fold.
Deoxyribonucleic acid (/diËÉksiËraÉªbÉµ.njuËËkleÉª.É¨k ËaesÉªd/ ; ËÃ¦SÉªD) dna is a molecule that carries most of the genetic instructions used in the, development functioning and reproduction of all known living organisms and many. virusesranscription is carried out by a DNA-dependent RNA polymerase that copies the sequence of a DNA strand into RNA. To begin transcribing a gene, the RNA polymerase binds to a sequence of DNA called a promoter and separates the DNA strands.
Introduction. DNA is the molecule which controls the synthesis of proteins. Proteins are used for growth and repair and also as enzymes, in which form they catalyse all other cellular activities. Thus DNA is able to exert a controlling influence over the whole cell and ultimately, the whole organism.The segments of DNA which hold the key to this control are the genes.roteins are used for growth and repair and also as enzymes, in which form they catalyse all other cellular activities. Thus DNA is able to exert a controlling influence over the whole cell and ultimately, the whole organism. The segments of DNA which hold the key to this control are the genes.