AAMC FL Practice Exam

What is the result of vasodilation in blood vessels?

1. Increased blood pressure

2. Increased blood flow

3. Decreased heart rate

4. Decreased blood flow

The correct answer is: Increased blood flow

Vasodilation refers to the widening of blood vessels, which occurs when the smooth muscles in the vessel walls relax. This relaxation leads to an increase in the diameter of the blood vessels. As a result, the resistance to blood flow decreases, allowing blood to flow more freely through the dilated vessels. This increased diameter leads to enhanced blood flow to various tissues and organs that require more oxygen and nutrients, particularly during times of increased metabolic activity, like exercise. In situations where vasodilation occurs, such as during exercise or in response to certain signaling molecules like nitric oxide, the increased blood flow can also aid in the removal of metabolic waste products. In contrast, increased blood pressure is typically associated with vasoconstriction, where blood vessels narrow and resistance increases. A decreased heart rate is generally not a direct result of vasodilation but is more related to the autonomic nervous system and cardiovascular reflexes. Decreased blood flow would occur if vasoconstriction were to take place rather than vasodilation, as narrowing would reduce the vessel's capacity to conduct blood.