No valves exist between the anterior vena cava and the heart, and the heartbeat tends to cause movement within this blood vessel. Another vessel, the posterior vena cava, carries blood from the lower half of the body to the heart.
The 2016 Hereford, Texas, population is 15,021. There are 2,447 people per square mile (population density).
Crockett County is a county located on the Edwards Plateau in the U.S. state of Texas. As of the 2010 census, its population was 3,719. The county seat is Ozona. The county was founded in 1875 and later organized in 1891.