Module 15: Cardiovascular System Flashcards
What is the name of the double walled sack that surrounds the heart?
Pericardium
What is the pericardium anchored by?
Ligaments and tissue to surrounding structures
Where is the endocardium located?
Lines the heart chambers, covers the valves, and continues into the vessels
What is the myocardium composed of and what layer of the heart wall is it?
Composed of cardiac muscle, forms the middle layer
What is the name of the connective tissue that covers the heart’s surface?
Fibrous pericardium
What are the names of the two upper chambers of the heart?
Atria
What are the names for the two lower chambers of the heart?
Ventricles
What is the name for the large vessels attach the heart that transport blood to and from the heart?
Great vessels
What are the atria separated by?
A common wall of myocardium called the interatrial septum
What is the function of the atria?
Receiving blood from the body or lungs
What is the function of the ventricles?
Serve as pumps, receiving blood from the atria and then pumping it either to the lungs (right ventricle) or the body (left ventricle)
What are the ventricles separated by?
Interventricular septum
What valves regulate flow between the atria and the ventricles?
Atrioventricular (AV) valves
What valves regulate flow between the ventricles and the great arteries?
Semilunar valves
What is the role of the tricuspid valve?
Right AV valve - Prevents backflow from the right ventricle to the right atrium
What is the role of the bicuspid valve?
Left AV valve - Prevents backflow from the left ventricle to the left atrium
What is the role of the pulmonary valve?
Prevents backflow from the pulmonary artery to the right ventricle
What is the role of the aortic valve?
Prevents backflow from the aorta to the left ventricle
What is the fibrous connective tissue which encircles each valve?
Skeleton of the heart
What is the function of the skeleton of the heart?
Supports heart, keeps valves from stretching, acts as an insulating barrier between the atria and ventricles
What is the heart’s own vascular system called?
Coronary circulation
What is the role of the coronary arteries?
Deliver oxygenated blood to the myocardium
What is the role of the cardiac veins?
Collect the deoxygenated blood
What is the role of the coronary sinus?
Returns the blood to the right atrium
When do the coronary arteries receive blood?
When the ventricles relax
Which part of the heart receives the most amount of blood?
The myocardium of the left ventricle
What does an electrocardiogram (ECG) do?
Records the electrical activity or impulses; It does not record the hearts contractions
What does the P wave represent?
Atrial depolarization
What does the PR interval represent?
The time it takes for the cardiac impulse to travel from the atria to the ventricles
What does the QRS complex represent?
Ventricular depolarization
What does the ST segment represent?
The end of ventricular depolarization and the beginning of ventricular repolarization
What does the T wave represent?
Ventricular repolarization
What is the cardiac cycle?
The series of events that occur from the beginning of one heartbeat to the beginning of the next
What is systole?
Contraction
What is diastole?
Relaxation
What is cardiac output (CO)?
The amount of blood the heart pumps in 1 minute
What is the stroke volume (SV)?
Amount of blood ejected with each heartbeat
How do you calculate cardiac output?
Heart rate x stroke volume
What is the average resting cardiac output?
Between 5 and 6 litres per minute
