Factors Affecting Blood Flow and Vascular Resistance The Poiseuille Equation

The video tutorial explains the factors affecting blood flow in the cardiovascular system using the Hagen Poiseuille equation. It highlights the importance of the pressure gradient and its role in blood flow, comparing scenarios of rest and exercise. The tutorial also discusses vascular resistance, focusing on blood viscosity, vessel length, and vessel diameter. It explains how these factors influence resistance and blood flow, with a detailed look at how vessel diameter is regulated through vasoconstriction and vasodilation.

What is the primary purpose of the Hagen-Poiseuille equation in the context of the cardiovascular system?

• To determine oxygen levels in blood

• To measure blood pressure

• To describe factors affecting blood flow

• To calculate the heart rate

Which factor is NOT directly related to vascular resistance?

• Pressure gradient

• Vessel diameter

• Blood viscosity

• Vessel length

How does an increase in the pressure gradient affect blood flow?

• Reverses blood flow direction

• Decreases blood flow

• Increases blood flow

• Has no effect on blood flow

What happens to blood flow when the heart contracts with more force during exercise?

• Blood flow increases

• Blood flow stops

• Blood flow remains constant

• Blood flow decreases

Which of the following increases vascular resistance?

• Decreased blood viscosity

• Shorter vessel length

• Increased vessel diameter

• Increased blood viscosity

What effect does dehydration have on blood viscosity?

• Decreases viscosity

• Increases viscosity

• No effect on viscosity

• Reverses viscosity

How does vessel length affect blood flow?

• Vessel length has no effect

• Longer vessels decrease blood flow

• Shorter vessels decrease blood flow

• Longer vessels increase blood flow

What is the effect of vasoconstriction on blood flow?

• Increases blood flow

• Decreases blood flow

• No change in blood flow

• Reverses blood flow

Which system primarily regulates vessel diameter?

• Sympathetic nervous system

• Endocrine system

• Respiratory system

• Digestive system

What happens to blood flow when vessel radius is increased?

• Blood flow decreases

• Blood flow increases

• Blood flow remains unchanged

• Blood flow stops