In certain cities, too, traditional farms and other forms of urban farming - such as crops grown on rooftops or vacant lots - may only be 60 to 100 miles away, close enough to compete with vertical farms. Vertical-farming projects have sprouted up in several North American cities as well as in the Netherlands, Scandinavia, Germany, Korea, Japan, Abu Dhabi and Singapore among others.
Deoxygenated blood enters the right atrium through three major veins: the superior and inferior vena cava and the coronary sinus. The superior vena cava returns all of the blood to the heart from tissues superior to the heart in the head, neck, arms and upper thorax. Likewise, the inferior vena cava returns blood to the heart from tissues inferior to the heart, including the legs, abdomen and lower thorax.
Blood vessels which carry blood back to the heart from the rest of the body are called veins. The main vein is the vena cava, which carries deoxygenated blood to the right atrium. The pulmonary vein carries oxygenated blood from the lungs to the left atrium.The arteries are blood vessels which carry blood away from the heart. The main artery is the aorta, which carries oxygenated blood from the heart to the rest of the body.The pulmonary artery carries deoxygenated blood from the right ventricle to the lungs.he main vein is the vena cava, which carries deoxygenated blood to the right atrium. The pulmonary vein carries oxygenated blood from the lungs to the left atrium. The arteries are blood vessels which carry blood away from the heart.