Deoxyribonucleic acid, or DNA, is a polymer of nucleotides linked together by specific bonds known as phosphodiester bridges. The phosphate group (PO3) of one nucleotide links to the hydroxyl group (OH) of the following nucleotide.Hundreds of millions of these linkages occur within the DNA polymer.he two DNA strands are held together by interchain hydrogen bonds. H-bonds pair the bases in one chain to the complementary bases in the other chain. (A/T and G/C).
The master circadian pacemaker in mammals is located in the suprachiasmatic nucleus in the rostroventral hypotha-lamus (Figure 2). Lesion studies identified it in 1972, and in vitro and in vivo functional studies, as well as transplant studies, have repeatedly corroborated the finding since then.
A pacemaker is an electronic device that provides an electrical signal to make the heart beat when itâs own, built-in pacemakers fail. The anatomical, built-in pacemakers provide whatâs called the âintrinsicâ rhythm, and they can be disrupted by various conditions â ischemia for example, or by an MI.acemakers can be either temporary or permanent. The temporary pacemakers that we see in the MICU are made up of a control box and one single output wire leading to the inner wall of the RV (thus called a ventricular wire, or âV-wireâ), and provide simple rate control by pacing the ventricles.