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).
Houston (/ËhjuËstÉn/ ( listen) HYOO-stÉn) is the most populous city in the state of Texas and the fourth-most populous city in the United States. With a census-estimated 2016 population of 2.303 million[5][6] within an area of 667 square miles (1,730 km2),[7] it is also the largest city in the southern United States[8] and the seat of Harris County.