Chapter 1 Flashcards
(80 cards)
What is the primary function of the heart?
To pump blood to meet the body’s metabolic needs.
The heart accomplishes this by beating 60 to 100 times per minute.
What is the average range of blood circulation per minute for the heart?
4 to 8 liters.
The heart pumps approximately 6,000 liters of blood each day.
What is the typical number of heartbeats per day for an average person?
Approximately 90,000 times.
This number can increase with stress or exertion.
Where is the heart located?
In the thoracic cavity, between the lungs in the mediastinum.
It is above the diaphragm, behind the sternum, and in front of the spine.
What structures surround the heart for protection?
Bony structures.
This bony cage also aids in CPR by allowing external chest compressions.
What are the coronary arteries responsible for?
Supplying blood to the heart muscle.
They are essential for the heart’s function and health.
What occurs in the cardiac cycle?
Different phases of heart contraction and relaxation.
Each phase corresponds to specific heart actions and functions.
Name the two types of cardiac cells.
Myocardial cells and pacemaker cells.
Myocardial cells are responsible for contraction, while pacemaker cells regulate heart rhythm.
What is the oxygen saturation of the heart’s chambers typically?
Varies depending on the chamber.
The right atrium has lower saturation compared to the left atrium.
What are the functions of heart valves?
Prevent backflow of blood and ensure unidirectional flow.
They open and close in response to pressure changes in the heart.
What is the relationship of the valves to heart sounds?
Valve closure produces heart sounds.
The ‘lub’ sound corresponds to the closure of the atrioventricular valves.
List the great vessels associated with the heart.
- Aorta
- Pulmonary arteries
- Pulmonary veins
- Superior vena cava
- Inferior vena cava
Each vessel has specific functions related to blood flow into or out of the heart.
What are the sympathetic and parasympathetic nervous systems responsible for?
Regulating heart rate and function.
The sympathetic system increases heart rate, while the parasympathetic system decreases it.
Describe the fight-or-flight response in relation to the heart.
Increases heart rate and blood flow during stress or danger.
This response is mediated by the sympathetic nervous system.
Describe the rest-and-digest response in relation to the heart.
Decreases heart rate and conserves energy.
This response is mediated by the parasympathetic nervous system.
What can cause a myocardial infarction (MI)?
Blocked coronary arteries.
This blockage can lead to insufficient blood supply to the heart muscle.
What is the significance of understanding heart anatomy for patients?
It helps them comprehend their medical conditions and treatments.
Education can alleviate anxiety and improve compliance with medical advice.
What is the base of the heart?
The top of the heart from which the great vessels emerge.
What is the apex of the heart?
The bottom pointy part of the heart that rests on the diaphragm.
How is the heart positioned in the chest?
The heart lies at an angle with the bottom pointing to the left.
What are the three layers of the heart?
- Epicardium: The outermost layer.
- Myocardium: The middle and thickest layer, made of muscle.
- Endocardium: The thin innermost layer lining the heart’s chambers.
What is the function of the pericardium?
A double-walled sac that encloses the heart, providing support and protection.
What is the purpose of pericardial fluid?
To minimize friction between the layers of the pericardium during heartbeats.
How many chambers does the heart have?
The heart has four chambers.