Functional groups are defined as specific groupings of atoms or bonds which are part of a larger hydrocarbon chain. It is necessary that you are able to recognize these groups by structure and by name. The ending of the name as a suffix tells the type of compound or functional group present.
[TA] a slight constriction of the aorta immediately distal to the left subclavian artery at the point of attachment of the ductus arteriosus. Synonym(s): isthmus aortae [TA], isthmus of aorta. A constriction in the fetal aorta between the ductus arteriosus and the left subclavian artery.
Inappropriate sinus tachycardia (IST) is a condition in which a person's heart rate, at rest and during exertion, is abnormally elevated for no apparent reason. People with IST often have resting heart rates greater than 100 beats per minute, and with even minimal exertion the heart rate often rises to very high levels.