Pressure, force and elasticity (Oct 2025)

Created by Ariel

p.2

What is the flow rate equation used to describe blood flow?

A. F = ∆P - R

B. F = ∆P * R

C. F = R/∆P

D. F = ∆P/R

E. F = R + ∆P

Select an answer

p.2

Explanation

The flow rate equation is defined as F = ∆P/R, where F is the flow rate, ∆P is the pressure difference, and R is the resistance to flow.

Click to see question

1 / 159

p.2

Flow rate equation (F = ∆P/R)

What is the flow rate equation used to describe blood flow?

p.2

Types of blood flow (laminar vs turbulent)

What are the two types of blood flow discussed in the lecture?

p.2

Importance of arterial blood pressure

What is the significance of arterial blood pressure?

p.2

Poiseuille's law

Which law describes the relationship between flow rate, pressure difference, and resistance?

p.2

Factors affecting venous return (VR)

What factor does NOT affect venous return (VR)?

p.3

Overview of Blood Vessels

What is the primary function of arteries in the circulatory system?

p.3

Veins as Blood Reservoirs

What percentage of the body's total blood do veins house?

p.3

Vascular Resistance

What is vascular resistance?

p.3

Veins and Venous Return

What is the role of veins in the circulatory system?

p.27

Physiological significance of elastic recoil in ar...

What happens to the arterial wall when pressure drops after ventricular contraction?

p.3

Poiseuille's law

What is Poiseuille's Law related to?

p.4

Factors affecting resistance (R) to blood flow

What primarily controls the rate of blood flow through tissues in the human body?

p.4

Pulmonary and systemic circuits

What are the main components of the circulatory system?

p.4

Importance of arterial blood pressure

What happens to blood flow during exercise compared to rest?

p.4

Factors affecting venous return

What is the role of the pressure gradient (ΔP) in the circulatory system?

p.4

Importance of arterial blood pressure

What does the graph mentioned in the text illustrate?

p.5

Flow rate equation (F = ∆P/R)

What are the two main factors that determine blood flow through a blood vessel?

p.5

Flow rate equation (F = ∆P/R)

What does the pressure difference (ΔP) in a blood vessel represent?

p.5

Factors affecting resistance (R) to blood flow

What does resistance in a blood vessel refer to?

p.6

Flow rate equation (F = ∆P/R)

What does the flow rate equation F = ΔP/R represent in the cardiovascular system?

p.6

Flow rate equation (F = ∆P/R)

What generates the pressure difference (ΔP) in the cardiovascular system?

p.6

Flow rate equation (F = ∆P/R)

How can the magnitude of ΔP be modified in the cardiovascular system?

p.6

Flow rate equation (F = ∆P/R)

What does the variable R represent in the flow rate equation F = ΔP/R?

p.6

Flow rate equation (F = ∆P/R)

Which system is involved in modifying the flow rate in the cardiovascular system?

p.6

Flow rate equation (F = ∆P/R)

What is the primary function of the flow rate equation in the cardiovascular system?

p.6

Flow rate equation (F = ∆P/R)

What role do hormones play in the flow rate equation F = ΔP/R?

p.7

Flow rate equation (F = ∆P/R)

What does the flow rate equation F = ΔP / R represent in the cardiovascular system?

p.7

Flow rate equation (F = ∆P/R)

In the flow rate equation, what does ΔP represent?

p.7

Flow rate equation (F = ∆P/R)

How does bulk flow relate to the flow rate equation?

p.7

Flow rate equation (F = ∆P/R)

What is the relationship between flow (F) and resistance (R) in the flow rate equation?

p.7

Flow rate equation (F = ∆P/R)

What does the term 'bulk flow' specifically refer to?

p.8

Flow rate equation (F = ∆P/R)

What does ΔP represent in the vascular system?

p.8

Factors affecting resistance (R) to blood flow

What is necessary to drive blood flow according to the text?

p.9

Importance of arterial blood pressure

Why is adequate blood pressure essential for the human body?

p.9

Importance of arterial blood pressure

What can result from reduced blood flow to an organ?

p.9

Importance of arterial blood pressure

What is atherosclerosis?

p.9

Importance of arterial blood pressure

Which organs are critically dependent on steady arterial blood supply?

p.9

Importance of arterial blood pressure

What is the consequence of atherosclerosis on blood flow?

p.10

Types of blood flow (laminar vs turbulent)

What characterizes laminar flow in blood vessels?

p.10

Types of blood flow (laminar vs turbulent)

What happens to blood flow in turbulent conditions?

p.10

Types of blood flow (laminar vs turbulent)

What is a common sound associated with turbulent flow in blood vessels?

p.10

Types of blood flow (laminar vs turbulent)

In laminar flow, where is the velocity of blood flow the greatest?

p.10

Types of blood flow (laminar vs turbulent)

What typically causes blood flow to become turbulent?

p.11

Types of blood flow (laminar vs turbulent)

What type of blood flow is indicated by a normal open valve?

p.11

Types of blood flow (laminar vs turbulent)

What is a characteristic of a stenotic valve?

p.11

Types of blood flow (laminar vs turbulent)

What happens when a valve is insufficient?

p.11

Types of blood flow (laminar vs turbulent)

What is the flow characteristic of a normal closed valve?

p.11

Types of blood flow (laminar vs turbulent)

What sound is associated with turbulent flow in a stenotic valve?

p.12

Pulmonary and systemic circuits

What type of system is the circulatory system classified as?

p.12

Pulmonary and systemic circuits

What are the two circuits of the circulatory system?

p.13

Pulmonary and systemic circuits

What is the starting point of the pulmonary circuit?

p.13

Pulmonary and systemic circuits

What type of blood vessels carry blood away from the heart in both the pulmonary and systemic circuits?

p.13

Pulmonary and systemic circuits

Where does the systemic circuit deliver oxygenated blood?

p.13

Pulmonary and systemic circuits

What is the endpoint of the systemic circuit?

p.13

Pulmonary and systemic circuits

What is the role of veins in the circulatory system?

p.14

Pulmonary and systemic circuits

What is the pressure gradient (ΔP) across the pulmonary circuit?

p.15

Importance of arterial blood pressure

What is the pressure gradient across the systemic system calculated as?

p.15

Importance of arterial blood pressure

What is the mean systemic arterial pressure (MAP) in this context?

p.15

Importance of arterial blood pressure

How does the pressure in the systemic circuit compare to the pulmonary circuit?

p.15

Factors affecting resistance (R) to blood flow

What does the pressure gradient (ΔP) indicate in the systemic system?

p.15

Factors affecting resistance (R) to blood flow

What happens to the pressure as blood flows through the systemic circuit?

p.16

Pulmonary and systemic circuits

What is the relationship between blood flow in the pulmonary and systemic circuits?

p.17

Factors affecting resistance (R) to blood flow

What does it indicate when flow is the same but average pressure (AP) is different in the systemic and pulmonary circuits?

p.18

Poiseuille's law

What type of flow does Poiseuille's law apply to?

p.18

Poiseuille's law

What does the variable 'L' represent in Poiseuille's law?

p.18

Factors affecting resistance (R) to blood flow

Which factor does NOT affect the resistance (R) in the cardiovascular system according to Poiseuille's law?

p.18

Poiseuille's law

What is the mathematical constant in Poiseuille's law?

p.18

Poiseuille's law

What does the variable 'r' represent in the formula for resistance according to Poiseuille's law?

p.19

Factors affecting resistance (R) to blood flow

How does the radius of a tube affect resistance to blood flow?

p.19

Factors affecting resistance (R) to blood flow

What happens to flow (F) when the radius of a tube is halved, given the same pressure gradient (ΔP)?

p.19

Poiseuille's law

What is the mathematical relationship that expresses resistance (R) in terms of radius (r)?

p.19

Factors affecting resistance (R) to blood flow

What effect does a smaller tube radius have on the wall surface area and frictional resistance to blood flow?

p.19

Importance of arterial blood pressure

In the context of blood flow, what does a pressure gradient (ΔP) refer to?

p.20

Factors affecting resistance (R) to blood flow

What happens to the flow rate when the radius of a tube is decreased by half?

p.21

Factors affecting resistance (R) to blood flow

What is the biggest physiological contributor to resistance in the vascular system?

p.21

Factors affecting resistance (R) to blood flow

How does atherosclerosis affect blood flow resistance?

p.21

Factors affecting resistance (R) to blood flow

What effect does obesity have on blood vessel length?

p.21

Factors affecting resistance (R) to blood flow

What happens to blood viscosity during anemia?

p.21

Factors affecting resistance (R) to blood flow

What effect does a decrease in temperature have on blood viscosity?

p.22

Types of blood flow (laminar vs turbulent)

What is the primary function of veins in the vascular system?

p.22

Types of blood flow (laminar vs turbulent)

What do capillaries primarily facilitate in the circulatory system?

p.22

Types of blood flow (laminar vs turbulent)

Which blood vessels connect capillaries with veins?

p.22

Types of blood flow (laminar vs turbulent)

What is the role of arterioles in the vascular system?

p.22

Types of blood flow (laminar vs turbulent)

What type of blood do arteries transport?

p.22

Types of blood flow (laminar vs turbulent)

What is the primary characteristic of blood flow in veins compared to arteries?

p.22

Factors affecting resistance (R) to blood flow

What is the relationship between arterioles and systemic resistance (R)?

p.23

Factors affecting resistance (R) to blood flow

How does arteriolar radius affect blood flow resistance?

p.23

Role of smooth muscle in arterioles

What happens during vasoconstriction?

p.23

Role of smooth muscle in arterioles

What is the role of smooth muscle in arterioles?

p.23

Role of smooth muscle in arterioles

What occurs during vasodilation?

p.23

Factors affecting resistance (R) to blood flow

What is the effect of smooth muscle contraction on arterioles?

p.24

Factors affecting resistance (R) to blood flow

What happens to the resistance (R) when smooth muscle cells in the arteriole contract?

p.25

Factors affecting resistance (R) to blood flow

What does Total Peripheral Resistance (TPR) refer to?

p.25

Factors affecting resistance (R) to blood flow

How does resistance in arteries affect blood flow to tissues?

p.25

Pulmonary and systemic circuits

What is the primary role of arteries in the systemic circuit?

p.26

Compliance and elastance of blood vessels

What is the primary difference between arteries and veins in terms of compliance?

p.26

Compliance and elastance of blood vessels

What does elastance refer to in blood vessels?

p.26

Compliance and elastance of blood vessels

How is compliance defined in the context of blood vessels?

p.26

Compliance and elastance of blood vessels

What is the formula for calculating compliance in blood vessels?

p.26

Compliance and elastance of blood vessels

What is the relationship between compliance and elastance in blood vessels?

p.27

Physiological significance of elastic recoil in ar...

What does high elastance in arteries indicate about their response to volume changes?

p.27

Physiological significance of elastic recoil in ar...

What is the role of elastic recoil during the diastole phase of the cardiac cycle?

p.27

Physiological significance of elastic recoil in ar...

What is the significance of the aortic valve being closed during diastole?

p.27

Physiological significance of elastic recoil in ar...

What is the primary characteristic of arteries that allows them to withstand high pressure during systole?

p.28

Physiological significance of elastic recoil in ar...

What is elastic recoil in the context of arterial walls?

p.28

Physiological significance of elastic recoil in ar...

How does elastic recoil affect blood flow during diastole?

p.28

Physiological significance of elastic recoil in ar...

What role does elastic recoil play in maintaining arterial pressure?

p.28

Physiological significance of elastic recoil in ar...

What happens to the artery during ventricular contraction?

p.28

Physiological significance of elastic recoil in ar...

What occurs during ventricular relaxation in relation to the artery?

p.29

Compliance and elastance of blood vessels

What does high compliance in veins indicate?

p.29

Importance of arterial blood pressure

What percentage of the body's blood volume is held in veins?

p.29

Factors affecting venous return (VR)

Why are veins referred to as capacitance vessels?

p.29

Compliance and elastance of blood vessels

What is the primary characteristic of veins compared to arteries?

p.29

Factors affecting venous return (VR)

What is the significance of veins being compliant?

p.30

Factors affecting venous return (VR)

What is venous return?

p.30

Factors affecting venous return (VR)

Which of the following factors does NOT affect venous return?

p.30

Factors affecting venous return (VR)

How does improving venous return affect cardiac output?

p.30

Factors affecting venous return (VR)

What role do skeletal muscle pumps play in venous return?

p.30

Factors affecting venous return (VR)

What is the effect of venoconstriction on venous return?

p.31

Factors affecting venous return (VR)

What role do one-way venous valves play in conjunction with the skeletal muscle pump?

p.31

Factors affecting venous return (VR)

What happens to the proximal and distal valves during skeletal muscle contraction?

p.31

Factors affecting venous return (VR)

What is the consequence of having incompetent venous valves?

p.31

Factors affecting venous return (VR)

What is the primary function of the skeletal muscle pump?

p.31

Factors affecting venous return (VR)

What occurs when skeletal muscles relax in relation to venous valves?

p.32

Role of smooth muscle in arterioles

What effect does inhalation have on the diaphragm?

p.32

Role of smooth muscle in arterioles

What happens to the chest during exhalation?

p.32

Role of smooth muscle in arterioles

What is the primary action of the intercostal muscles during inhalation?

p.32

Role of smooth muscle in arterioles

What occurs to the diaphragm during exhalation?

p.32

Role of smooth muscle in arterioles

What is the overall effect of the respiratory pump?

p.33

Factors affecting venous return (VR)

How does inhalation affect venous return?

p.33

Factors affecting venous return (VR)

What happens to pressure in the thoracic cavity during inhalation?

p.33

Factors affecting venous return (VR)

What is the effect of abdominal pressure during inhalation?

p.33

Factors affecting venous return (VR)

What mechanism is described as the 'respiratory pump'?

p.33

Factors affecting venous return (VR)

What is the primary effect of unequal pressure during inhalation?

p.34

Factors affecting venous return (VR)

What physiological effect does stress have on venous return?

p.34

Factors affecting venous return (VR)

What happens to venous compliance during sympathetic activation due to stress?

p.34

Factors affecting venous return (VR)

What is the result of increased venous pressure on blood flow to the right atrium?

p.34

Factors affecting venous return (VR)

Which physiological components are increased as a result of improved venous return?

p.34

Factors affecting venous return (VR)

What initiates the process of increased venous return during stress?

p.35

Factors affecting venous return (VR)

What effect does increased activity of the muscle pump have on venous pressure?

p.35

Factors affecting venous return (VR)

How does blood volume affect mean arterial pressure (MAP)?

p.35

Factors affecting resistance (R) to blood flow

What is the relationship between venous compliance and venous pressure?

p.35

Factors affecting venous return (VR)

What role do sympathetic nerves play in venous pressure?

p.35

Mean arterial pressure (MAP)

What is the final outcome of increased stroke volume (SV) on mean arterial pressure (MAP)?

p.36

Pulmonary and systemic circuits

What does the equation CO = HR x SV represent in the systemic circuit?

p.37

Importance of arterial blood pressure

What are the components of a homeostatic control system?

p.37

Importance of arterial blood pressure

What is the primary mechanism for short-term regulation of Mean Arterial Pressure (MAP)?

p.37

Importance of arterial blood pressure

How does the renal system contribute to long-term regulation of MAP?

p.37

Importance of arterial blood pressure

What is the role of the fast response in regulating blood pressure?

p.37

Importance of arterial blood pressure

Which of the following best describes the slow response mechanism in blood pressure regulation?

p.38

Flow rate equation (F = ∆P/R)

What is the flow equation in relation to blood flow?

p.38

Poiseuille's law

What does Poiseuille's law describe?

p.38

Factors affecting resistance (R) to blood flow

Why is the radius of arterioles a key contributor to blood flow resistance?

p.38

Types of blood flow (laminar vs turbulent)

What is the difference between laminar and turbulent flow in blood vessels?

p.38

Compliance and elastance of blood vessels

What do compliance and elastance of a blood vessel refer to?

p.38

Role of smooth muscle in arterioles

How does the contractile activity of smooth muscle in arterioles affect resistance to blood flow?

p.38

Factors affecting venous return

What is venous return?

p.38

Factors affecting venous return

How can compliance in a vein change through sympathetic stimulation?

p.38

Factors affecting venous return

How does improved venous return increase mean arterial pressure (MAP)?

Study Smarter, Not Harder