Barstow is a city in San Bernardino County, California, United States. The population was 22,639 at the 2010 census, up from 21,119 at the 2000 census. Barstow is located 55 miles (89 km) north of San Bernardino. Barstow is a major transportation center for the Riverside-San Bernardino metropolitan area. Several major highways including Interstate 15 and Interstate 40 converge in the city. It is the site of a large rail classification yard, belonging to the BNSF Railway.
1 Capillaries are the smallest blood vessels. 2  They connect to the arteries and the veins. 3  Capillaries are extremely small tubes that average 6 to 8 micron in size; they are too small to see without a microscope.xygen rich blood is pumped out of the left ventricle of the heart into the aorta, which is the largest artery in the body. The oxygen rich blood travels through the aorta into smaller arteries. The capillaries sit between the arteries and the veins, connecting the two together and acting as an exchange stop.
Veins and arteries are both types of blood vessels but arteries carry blood away from the heart to the rest of the body while veins carry blood to the heart from the rest of the body. All arteries except the pulmonary and umbilical arteries carry oxygenated blood while all veins carry deoxygenated blood. The arteries are basis of the circulatory system and their main function is to deliver oxygen and nutrients through blood to all the cells in the body.