In biology, an adaptation, also called an adaptive trait, is a trait with a current functional role in the life of an organism that is maintained and evolved by means of natural selection. Adaptation refers to both the current state of being adapted and to the dynamic evolutionary process that leads to the adaptation.
Computed Tomography Angiogram (CT Angiogram). Guide. A computed tomography angiogram (CT angiogram) is a test that uses X-rays to provide detailed pictures of the heart and the blood vessels that go to the heart, lung, brain, kidneys, head, neck, legs, and arms.
CT Pulmonary Angiogram. CT Pulmonary Angiogram (CTPA) is a special test used primarily to look for the presence of pulmonary embolus (blood clots in the lung). How the Test is Performed. CT Pulmonary Angiogram (CTPA) is performed in the radiology department scanning room, with the patient lying flat (supine) on a CT table.