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.
Julia Plecher, an avid participant of Stiletto Races, holds the fastest Guinness World Record of running the 100m in heels with a time of 14.53 seconds. Thatâs only 5 seconds slower than Usainâs World Record and she even avoided falling on her face.amaican sprinter and Olympic champion, Usain Bolt holds the World Record for fastest 100m of 9.58 seconds.