Species range in size from the hefty Common Raven (Corvus corax), at 1.5 kg (3 lb 5 oz) and 70 cm (2 ft 3 in), to the diminutive Short-tailed Pygmy Tyrant (Myiornis ecaudatus), at just 4.2 g (0.14 oz) and 6.5 cm (2 Â½ in).
The heart receives its own supply of blood from the coronary arteries. Two major coronary arteries branch off from the aorta near the point where the aorta and the left ventricle meet. These arteries and their branches supply all parts of the heart muscle with blood.hen the coronary arteries narrow to the point that blood flow to the heart muscle is limited (coronary artery disease), collateral vessels may enlarge and become active.
The coronary arteries extend from the aorta to the heart walls supplying blood to the atria, ventricles, and septum of the heart. The coronary arteries supply oxygenated and nutrient filled blood to the heart muscle. There are two main coronary arteries: right coronary artery and left coronary artery.oronary Arteries: Branches. 1  Right Coronary Artery-Supplies oxygenated blood to the walls of the ventricles and the right atrium. 2  Posterior Descending Artery-Supplies oxygenated blood to the inferior wall of the left ventricle and the inferior portion of the septum.