What is Pericardium, definition and function. Pericardium is a tough, two-layer membranous sac that encloses the HEART. The pericardiumâs fibrous outer layer, called the fibrous pericardium, protects the heart from contact with the chest wall and other structures in the chest, including the LUNGS and the sternum.he inner layer of the pericardium is a filmy envelope. Its two surfaces are the parietal pericardium, which contacts the fibrous pericardium, and the epicardium, which covers the MYOCARDIUM somewhat like a wet tissue. Inside the envelope is a watery fluid that lubricates the heart.
Roman Empire Timeline. Timeline Description: The Roman Empire was one of the greatest civilizations in history. It began in Rome in 753 BC. Rome controlled over two million square miles stretching from the Rhine River to Egypt and from Britain to Asia Minor. This timeline highlights the major events in the history of Ancient Rome.
The Great Schism of late Middle Ages was the most important event of history that brought about a change in the social conditions of Europe along with the decreasing power of the Church. The Fall of Western Roman Empire (476 AD). The fall of Western Roman Empire is considered as the beginning of the Middle Ages. The last Roman emperor was Julius Nepos who was nominated by Eastern Emperor Zeno. Nepoâs rebellion magister militum Orestes dethroned Julius Nepos and declared his own son Romulus Augustus as the new Emperor of the Western Roman Empire.