Cardiac Anatomy & Physiology Flashcards

What chamber of the heart receives oxygenated blood from the lungs?

Answer: Left atrium

The left atrium is one of the heart's four chambers, specifically responsible for receiving oxygenated blood. This blood returns from the lungs via the pulmonary veins after being enriched with oxygen. From the left atrium, the oxygen-rich blood then flows into the left ventricle, ready to be pumped out to the rest of the body.

What structure separates the left and right sides of the heart?

Answer: Septum

The septum is a muscular wall that effectively divides the heart into its left and right sides. This crucial structure prevents the mixing of oxygenated blood (on the left side) with deoxygenated blood (on the right side). By maintaining separate blood flows, the septum ensures the efficient circulation of blood throughout the body and to the lungs.

Which valve prevents backflow of blood into the left atrium?

Answer: Mitral valve

The mitral valve, also known as the bicuspid valve, is located between the left atrium and the left ventricle. Its primary function is to open and allow oxygenated blood to flow from the left atrium into the left ventricle during diastole. During ventricular contraction (systole), the mitral valve closes tightly to prevent the backflow of blood into the left atrium, ensuring unidirectional flow towards the aorta.

What is the function of the right ventricle?

Answer: Pumps blood to the lungs

The right ventricle is one of the heart's two lower chambers, specifically tasked with pumping deoxygenated blood. It receives this blood from the right atrium and then contracts forcefully to push it into the pulmonary artery. This artery then carries the blood to the lungs, where it can pick up oxygen and release carbon dioxide.

Where does the heart's electrical impulse originate?

Answer: Sinoatrial node

The heart's electrical impulse originates in the sinoatrial (SA) node, often referred to as the heart's natural pacemaker. Located in the upper part of the right atrium, the SA node spontaneously generates electrical signals that initiate each heartbeat. These impulses then spread throughout the atria and ventricles, coordinating the rhythmic contraction and relaxation of the heart muscle.

Which part of the heart has the thickest wall?

Answer: Left ventricle

The left ventricle possesses the thickest muscular wall of all four heart chambers. This robust structure is necessary because it is responsible for pumping oxygenated blood with immense force into the aorta, which then distributes it throughout the entire systemic circulation of the body. The high pressure required for this systemic circulation necessitates a powerful and thick-walled ventricle.

What vessels supply blood to the heart muscle?

Answer: Coronary arteries

The heart muscle itself, known as the myocardium, requires a constant and rich supply of oxygen and nutrients to function continuously. This vital blood supply is delivered by the coronary arteries, which branch off the aorta near its origin. These arteries encircle the heart, providing blood to its various regions, and any blockage can lead to serious conditions like a heart attack.

What phase of the cardiac cycle involves ventricular contraction?

Answer: Systole

Systole is the phase of the cardiac cycle characterized by the contraction of the heart muscle, during which blood is pumped out of the chambers. Specifically, ventricular systole involves the forceful contraction of the ventricles, ejecting blood into the pulmonary artery (from the right ventricle) and the aorta (from the left ventricle). This contraction generates the pressure necessary to circulate blood throughout the body and lungs.

What is the function of the pericardium?

Answer: Protects and anchors the heart

The pericardium is a double-layered sac that encloses the heart and the roots of the great vessels. Its primary functions include protecting the heart from infection and trauma, anchoring it within the chest cavity to prevent excessive movement, and providing lubrication to reduce friction during heartbeats. The fluid within the pericardial sac allows the heart to beat smoothly within its protective enclosure.