10 Questions
What are the two upper chambers of the heart called?
Atria
Which layer of the heart is composed of cardiac muscle cells that contract rhythmically?
Myocardium
Where is the heart located in the body?
Between the lungs in the mediastinal cavity of the thorax
Which chambers of the heart pump blood to the lungs?
Right atrium and right ventricle
What is the function of the heart valves?
Ensuring one-way flow of blood through the heart
What is the function of the pulmonary valve?
Prevent blood from flowing backwards when the heart contracts
Which node initiates the heart's electrical impulses?
Sinoatrial (SA) node
Where do the coronary arteries branch off from to supply blood to the heart muscle?
Aorta
What is the role of the aortic valve in the heart's function?
Send impulses to the ventricles
Which structure ensures that blood is pumped efficiently throughout the body?
Pulmonary valve
Study Notes
Heart Anatomy
The heart is the key organ of the circulatory system and is responsible for pumping blood throughout the body. It is roughly the size of an adult's clenched fist, weighing around 350g, and is located between the lungs in the mediastinal cavity of the thorax. The heart has four chambers: two upper chambers called the atria, and two lower chambers called the ventricles. The heart is enclosed in the mediastinal cavity of the thorax between the lungs, extending downwards on the left between the second and fifth intercostal space.
Heart Layers
The heart is composed of two main layers: the myocardium and the endocardium. The myocardium is the middle muscular layer, made up of cardiac muscle cells, that contracts rhythmically and autonomously. The endocardium is the inner lining of the heart, which is responsible for the smooth flow of blood through the heart's chambers.
Heart Chambers
The heart has four chambers: two atria and two ventricles. The right atrium and right ventricle pump blood to the lungs, while the left atrium and left ventricle pump blood to the rest of the body. The atria are smaller than the ventricles and serve as receiving chambers for blood returning to the heart.
Heart Valves
The heart has four valves that ensure the one-way flow of blood through the heart. The tricuspid valve sits between the right atrium and right ventricle, and the mitral valve sits between the left atrium and left ventricle. The pulmonary valve sits between the right ventricle and the pulmonary artery, and the aortic valve sits between the left ventricle and the aorta. These valves prevent blood from flowing backwards when the heart contracts, ensuring that blood is pumped efficiently throughout the body.
Heart Nodes
The heart has two small masses of specialized conductive tissue called the sinoatrial (SA) node and the atrioventricular (AV) node. The SA node initiates the heart's electrical impulses, which trigger the heart to contract. These impulses then pass through the AV node, which sends them to the ventricles, causing them to contract in a coordinated manner.
Heart Blood Supply
The heart receives its own blood supply from the coronary arteries. These arteries branch off from the aorta and supply blood to the heart muscle, providing the oxygen and nutrients the heart needs to function properly.
Understanding the anatomy of the heart is crucial for understanding its function and potential health issues. The heart's intricate system of muscle layers, chambers, valves, and nodes work together to ensure the continuous circulation of blood in the body, forming the cardiac cycle.
Test your knowledge on the anatomy of the heart, including its layers, chambers, valves, nodes, and blood supply. Understand the essential structures and functions that make the heart a vital organ in the circulatory system.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
