If radius of a vessel is doubled then the blood flow is increased by?
Correct Answer: 16 times
Description: Ans. B 16 timesRef: Ganong: 26th ed. P 563* The influence of lumen diameter on resistance is dramatic. This is because resistance is inversely proportional to the radius of the blood vessel (one-half of the vessels diameter) raised to the fourth power (R=1/r4).* This means, that if an artery or arteriole constricts to one-half of its original radius, the resistance to flow will increase 16 times. And if an artery or arteriole dilates to twice its initial radius, then resistance in the vessel will decrease to 1/16 of its original value and flow will increase 16 times.
Category:
Physiology
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now