Cardiovascular System Flashcards
(121 cards)
What is the size of the heart?
Approximately the size of a clenched fist.
Where is the heart located?
Within the inferior mediastinum, between the lungs.
What are the two main layers of the pericardium?
- Fibrous pericardium
- Serous pericardium
What is the function of the fibrous pericardium?
Provides a tough, loose-fitting, and inelastic sac around the heart.
What is the pericardial space?
The space between the parietal and visceral layers of the serous pericardium containing 10-15 ml of pericardial fluid.
What are the three layers of the heart walls?
- Epicardium (visceral pericardium)
- Myocardium
- Endocardium
What is the myocardium?
Thick bundles of cardiac muscle that contract.
What is the role of the endocardium?
A thin layer that lines the heart chambers and is continuous with the linings of vessels.
How many chambers does the heart have?
Four chambers: two atria and two ventricles.
What are the names of the heart valves?
- Atrioventricular valves
- Semilunar valves
What is the tricuspid valve?
The right atrioventricular valve with three cusps.
What is the mitral valve?
The left atrioventricular valve with two cusps, also known as the bicuspid valve.
What is the pulmonary circuit?
Circuit that returns deoxygenated blood to the right side of the heart.
What does the systemic circuit do?
Returns oxygenated blood to the left side of the heart.
What are the components of the coronary circuit?
- Coronary arteries
- Coronary veins
What is aerobic metabolism?
Occurs when O2 is present and is necessary for the metabolic function of the heart.
What is myoglobin’s role in the heart?
Transfers oxygen from the blood to muscle and stores reserve oxygen.
What can occur if a part of the heart is oxygen-deprived for too long?
Myocardial infarction (heart attack).
What does anaerobic respiration provide?
Additional energy for brief periods of oxygen deprivation.
What is the sinoatrial node (SA node)?
The pacemaker of the heart, located in the right atrium.
What is the function of the atrioventricular node (AV node)?
Acts as a pacemaker with a slower rate than the SA node, allowing for optimal filling time for ventricles.
What is the Bundle of His?
Conducts electrical depolarization from the AV node to the ventricles.
What do Purkinje fibres do?
Conduct electrical depolarization into the ventricles, causing contraction.
Fill in the blank: The heart’s intrinsic conduction system sets the basic _______.
[rhythm]