Lecture 4 - Respiration 2 and CV 1

What are the roles of the cardiovascular (CV) system?

1. Deliver oxygen and fuel to activate tissues 2. Transports blood to the lungs for oxygenation 3. Remove metabolic byproducts from working muscle 4. Regulate body temperature, fluid balance, pH, etc. 5. Transport hormones, the body’s chemical messages.

What is the function of the vena cava in the cardiovascular system?

The vena cava transports deoxygenated blood from the body back to the right atrium of the heart.

What is cardiac output (Q)?

The amount of blood the heart pumps in one minute.

What is the equation for blood pressure (BP)?

BP = Cardiac Output (CO) x Total Peripheral Resistance (TPR).

What do baroreceptors sense?

Baroreceptors sense changes in blood pressure by detecting stretch in the arterial walls.

What is the function of skeletal muscle pumps in the venous system?

Skeletal muscle pumps help increase venous return by contracting muscles which compress veins.

What is Ohm's Law in relation to blood flow?

Flow = Change in pressure / resistance.

What are resistance vessels in the cardiovascular system?

Arteries and arterioles, which are responsible for regulating blood flow and pressure.

What is venous pooling?

A condition where blood collects in the veins, especially when standing still for a long time, potentially leading to fainting.

What is the role of the autonomic nervous system in blood pressure regulation during exercise?

The autonomic nervous system regulates heart rate and blood vessel constriction to maintain blood flow and pressure during exercise.

What does the Poiseuille’s Equation describe?

It's a formula that relates the flow of fluid through a pipe to the pressure drop along the pipe, revealing how factors like radius and viscosity affect blood flow.

What happens to cardiac output during microgravity conditions, such as space flight?

Cardiac output increases due to the removal of gravitational forces, but prolonged exposure can decrease plasma volume and heart mass.

What does the term 'venous tone' refer to?

The state of tension or constriction in the veins, regulated by the smooth muscle and influenced by the sympathetic nervous system.

What is the function of arterial chemoreceptors?

They sense changes in blood pH and local metabolites, such as lactate and hydrogen ions, to help regulate respiration and cardiovascular responses.

What is Wigger’s Diagram used for?

It is a graphical representation that illustrates the relationship between various cardiovascular events, including heart sounds and pressure changes, during the cardiac cycle.

Define stroke volume (SV).

The volume of blood pumped from the left ventricle of the heart with each heartbeat.

What occurs during upright posture regarding blood flow?

Upright posture can lead to lower central blood volume and decreased blood pressure, risking insufficient blood supply to the brain.

What are capacitance vessels?

Veins and venules that can expand to hold a larger volume of blood, thus acting as a reservoir.

What is VO2 and why is it significant?

VO2 refers to oxygen consumption, which is critical for assessing aerobic fitness and cardiovascular efficiency.

What is the significance of one-way valves in veins?

They prevent backflow of blood, ensuring unidirectional flow toward the heart.