For many true experimental designs, pretest-posttest designs are the preferred method to compare participant groups and measure the degree of change occurring as a result of treatments or interventions.
Itâs important to note that the flush caused by niacin is not harmful or dangerous. It is actually a sign of improved blood flow and circulation. Also niacin oxygenates the blood. When you get a niacin âflushâ it is an indication that the niacin is causing small blood vessels in your body to expand in size.Many of your small blood vessels, called capillaries, are so small that blood cells can only go through them in single file or if they are flexible enough to fold over.t is actually a sign of improved blood flow and circulation. Also niacin oxygenates the blood. When you get a niacin âflushâ it is an indication that the niacin is causing small blood vessels in your body to expand in size.
Finally, the arteries transport blood from the heart. Before we proceed with the functions of the body parts, let us start learning about the blood vessels diameter. The Diameter of Blood Vessels. What is the diameter of blood vessels? The diameter of blood vessels ranges from 8 micrometer to 25000 micrometer. The type of blood vessels that has the smallest diameter is the capillary while the type with the largest diameter is the artery. The artery also has the thickest wall and the capillary has the thinnest wall. Arteries can be classified into two types, namely the large arteries and the arterioles.