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.
Arteries (in red) are the blood vessels that deliver blood to the body. Veins (in blue) are the blood vessels that return blood to the heart. Deep veins, located in the center of the leg near the leg bones, are enclosed by muscle.hroughout the body, the arteries (in red) deliver oxygenated blood and nutrients to all of the bodyâs tissues, and the veins (in blue) return oxygen-poor blood back to the heart. The aorta is the large artery leaving the heart.