Most myocardial infarction is caused by a fibrillation b blo

Most myocardial infarction is caused by: a. fibrillation b. blocked blood flow c. cell death d. heart murmurs e. electrical shock Arteries in the head and neck must contain valves because blood is flowing away from gravitational pull. a. true, otherwise blood could not go up the neck and into the head b. true, and in fact all arteries have valves c. false, arterial blood pressure is sufficiently high that valves are unnecessary You have moved to the high Andean mountains to study high altitude physiology. After a months you notice that you have higher blood pressure then before. The best explanation for this change in blood pressure is you have had an increased in........ a. vessel length b. blood viscosity c. blood vessel diameter d. a and b e. all are correct

Solution

Most myocardial infarct is caused by blocked blood flow .Infarct is the cell death caused by lack of oxygen supply .

Arteriol blood pressure is high to pump blood.Artery walls are more thick, elastic and muscular to withstand this high pressure.