Submit. Â· just now. Report Abuse. when a rock is subjected to severe heat, then dramatic cooling onion weathering takes place. This is a form of physical weathering. The sudden change of temperature weakens the outer layer of rock and it will crumble away, this happens to rocks in the desert.
Definition. Common arterial trunk (CAT) is characterized by a single arterial trunk that arises from the base of the heart and gives origin to the systemic, coronary and pulmonary circulation. A large ventricular septal defect (VSD) is almost always present.
An artery is an elastic blood vessel that transports blood away from the heart. There are two main types of arteries: pulmonary arteries and systemic arteries. Pulmonary arteries carry blood from the heart to the lungs where the blood picks up oxygen.