connective The outer layer of a blood vessel (artery or vein) is called the tunica externa or tunica adventitia.See http://training.seer.cancer.gov/module_anatomy/unit7_3_ca â¦ rdvasc_blood1_classification.html pericardium is the layer of the blood vessel that is made of tough  connective tissue.onnective The outer layer of a blood vessel (artery or vein) is called the tunica externa or tunica adventitia.
As of June 2000, the fastest running human is Michael Johnson, the American track and field star who on August 1, 1996 set the world record of running 200 meters in 19.32 seconds.
This is regarded as the World Record, according to the International Association of Athletics â¦ Federations. Geoffrey Mutai of Kenya ran faster (2:03:02) at Boston Marathon on April 18th, 2011, but the legendary Boston course does not meet IAAF layout standards. The fastest marathon time run by a woman is 2:15:25.