Cardiac System. Flashcards
Structure/Pathway of Blood. Cardiac Conduction. Nural Control. Hormonal Control.. HR x SV = Q. Cardiovascular Drift. Starling's Law.
Label the Pathway of Blood.
- Vena Cava.
- RIght Atrium.
- Tricuspid Valve.
- Right Ventricle.
- Semi Lunar Valve.
- Pulmonary Artery.
- Lungs.
- Pulmonary Vein.
- Left Atrium.
- Bicuspid Valve.
- Left Ventricle.
- Semi Lunar Valve.
- Aorta.
Label the Cardiac Conduction System.
- Sinotrial [SA] Node.
- Atrioventricular [AV] Node.
- Bundle of His.
- Bundle Branches.
- Purkinje Fibres.
Describe how the Cardiac Conduction System causes the Heart to Contract.
The CCS sends electrical signals that make the heart contract.
The signals start at the SA node travel through the Atria and reach the AV node. The signal passes through bundle branches and Purkinje Fibres which cause the ventricles to contract.
Whys is there a delay at the AV Node?
The 0.1 second delay allows the Atria to finish contracting and the blood to have moved down.
What is the role of Chemoreceptors?
Detect increased acidity levels and chemical changes caused by CO2 and removes carbon dioxide.
Where are Chemoreceptors located?
Located in the Aortic Arch and Cartoid Arteries.
What is the response to detected increases in acidity levels?
A sympathetic response.
An increase in Heart Rate.
What is the role of Proprioceptors?
Detects movements in joints and muscles and provides oxygen.
Where are Proprioceptors located?
Located in Muscles and Joints.
What is the response to detected movement?
A sympathetic response.
An increase in Heart Rate.
What is the role of Baroreceptors?
They detect increases in blood pressure.
Where are Baroreceptors located?
Located in the Aortic Arch and Cartoid Arteries.
What is the response to detected increases in blood pressure?
A parasympathetic response.
A decrease in Heart Rate.
Define Sympathetic Response.
Increase.
Define Parasympathetic Response.
Slow it down.
Decrease.
Are neural responses proportional?
Yes.
What is the response to Exercise Intensity?
The more CO2, movement, and blood [pressure that is detected, the greater the response will be.
Where is Adrenaline released from?
The sympathetic nerves and the Adrenal gland.
Where is the Adrenal Gland?
Located at the top of the kidney.
Define Antisipatory Rise.
Before the start of exercise your heart rate will rise sligtly.
Your body ‘knows’ it is about to exercise, so it releases adrenaline.
Define Myogenic.
The ability to generate it’s own electrical impulse.
Define Systole.
The heart contracts.
Define Diastole.
The heart relaxes.
Explain Starling’s Law.
Starling’s Law describes the between the volume of blood that fills the heart during diastole, the greater the force of contraction during systole.
This allows the heart to adapt to changes in blood volume and pump out an appropriate amount of blood to meet the body’s needs.
Define Ejection Fraction.
The percentage of blood pumped out of the left ventricle per beat, in relation to how much was actually there.
What is the calculation for Ejection Fraction?
The total amount of blood in the Ventricle.
Define Heart Rate.
Number of times the heart beats per minute.
Define Stroke Volume.
The volume of blood pumped out of the heart per beat.
Define Cardiac Output.
The volume of blood pumped out per minute.
What is the calculation for Cardiac Output?
Heart Rate x Stroke Volume = Cardiac Output.
Describe the Difference in Cardiac Output between a Trained and an Untrained person.
Trained Individuals have a higher Cardiac Output compared to Untrained Individuals.
This is because regular exercise and training can increase the size and strength of the heart, allowing it to pump a high volume of blood per beat.
When does Cardiovascular drift happen?
Cardiovascular drift happens after 10-20 minutes of steady-state exercise.
What is a Cardiovascular Drift?
Less filling of the heart.
Cardiac muscles stretch less.
The resulting force of contraction decreases.
Decreased stroke volume / Ejection fraction.
Describe how Cardiovascular Drift may result in Lower Performance Levels.
Cardiovascular Drift happens during prolonged exercise.
During exercise for long periods of time, heart rate increases and stroke volume decreases. This can lead to a decrease in cardiac output and a lower delivery of oxygen to our muscles.
