Final answer:
Vasodilation is the widening of the blood vessels to increase blood flow and decrease blood pressure, counterbalancing vasoconstriction. When blood pressure increases by 50%, blood vessels must adapt through dilation to maintain proper blood flow. Extensive narrowing from plaque buildup may lead to cardiovascular diseases like hypertension.
Step-by-step explanation:
In biology, vasodilation refers to the widening of blood vessels, which increases blood flow and reduces blood pressure. This process occurs when the smooth muscles in the blood vessel walls relax. Normally, the balance of vasodilation and vasoconstriction, the narrowing of blood vessels, regulates blood pressure and distribution of blood throughout the body.
Considering a situation where normal blood pressure has increased by 50%, to find the factor by which the average radii of blood vessels have increased, one should refer to Poiseuille’s Law which relates the radius of blood vessels to the pressure difference across the circulatory system. For instance, if the pressure difference doubles, the radius of the blood vessels must increase by a factor that maintains the balance of this pressure difference, ensuring that the blood flow is not compromised. This is a simplification as cardiovascular dynamics can be rather complex and involve multiple factors.
Blood vessels that cannot compensate for pressure changes by dilation or vasoconstriction may experience stress leading to potential damage. According to LibreTexts, arteries can adapt to an increase in size, but plaque buildup might eventually narrow them significantly, potentially leading to cardiovascular diseases (CVD) such as hypertension or blockages.