A: Nucleic acids are made up of monomers called nucleotides. Each nucleotide consists of a five-carbon sugar, a phosphate group and a nitrogenous base. Repeating nucleotides create nucleic acids such as DNA, or deoxyribonucleic acid, and RNA, or ribonucleic acid.
Pain and discomfort are the main symptoms of angina. Angina often is described as pressure, squeezing, burning, or tightness in the chest. The pain or discomfort usually starts behind the breastbone.Pain from angina also can occur in the arms, shoulders, neck, jaw, throat, or back.ngina often is described as pressure, squeezing, burning, or tightness in the chest. The pain or discomfort usually starts behind the breastbone. Pain from angina also can occur in the arms, shoulders, neck, jaw, throat, or back.
Angina is temporary pain or discomfort in the chest that occurs when not enough oxygen-carrying blood reaches your heart muscle. (The term angina means pain, while pectoris refers to the chest.) Sometimes angina feels like heartburn, the similar sensations you may get after eating a heavy meal. But if you feel this pain regularly, it may be a symptom of heart disease.