Risk which is common to an entire class of assets or liabilities. The value of investments may decline over a given time period simply because of economic changes or other events that impact large portions of the market.
Properties of the alpha-helix. 1  The structure repeats itself every 5.4 Angstroms along the helix axis, ie we say that the alpha-helix has a pitch of 5.4 Angstroms. Alpha-helices have 3.6 amino acid residues per turn, ie a helix 36 amino acids long would form 10 turns.
Double strand of polynucleotides. The double helix of the complete DNA molecule resembles a spiral staircase, with two sugar phosphate backbones and the paired bases in the centre of the helix. This structure explains two of the most important properties of the molecule.ach of the sugar groups in this sugar-phosphate backbone is linked to one of the four nitrogenous bases. Strand of polynucleotides. DNA's ability to store-and transmit-information lies in the fact that it consists of two polynucleotide strands that twist around each other to form a double-stranded helix.