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.
Arteries (from Greek á¼ÏÏÎ·ÏÎ¯Î± (artÄria), meaning windpipe, artery) are blood vessels that carry blood away from the heart. While most arteries carry oxygenated blood, there are two exceptions to this, the pulmonary and the umbilical arteries.