Easy diagram of heart

The Cardiac Cycle The cardiac cycle has 2 main phases: • Systole • Diastole Systole and diastole are defined by whether the heart is depolarized (contracting) or repolarized (relaxed). This lecture will walk you through one cycle of the heart. We will use a step-by-step diagram that will be sure to have you understanding the cardiac cycle in minutes! But if that wasn’t enough….. We will also review the order of the blood flow through the heart step-by-step. As we walk through the cardiac cycle, we will also review the conduction system of the heart including the SA node, AV node, bundle of His, right and left bundle branches, and Purkinje fibers. So what does this mean for you?! In just this one lecture you will learn how the cardiac cycle, blood flow through the heart, and the cardiac conduction system all come together! Make sure to also check how the cardiac cycle applies to the different parts of an ECG/EKG waveform! The “ EKGs Made Easy” lecture explains how the P wave, PR segment, QRS complex, ST segment, T wave, and TP segment are formed! Anatomy of the Heart Before we get started, let’s briefly review the anatomy of the heart. If you want more information on the anatomy of the heart, make sure to check out the step-by-step guide below! Heart Anatomy: Labeled Diagram, Structures, Function, and Blood Flow It is filled with memory tricks to remember the main structures of the heart! Cardiac Chambers There are 4 chambers of the heart: • Right Atrium • Right Ventricle •...

Day after day, your heart beats about 100,000 times, pumping 2,000 gallons of blood through 60,000 miles of blood vessels. If one of your organs is working that hard, it makes sense to learn about how it functions! This science quiz game will help you identify the parts of the human heart with ease. Blood comes in through veins and exists via arteries—to control the direction of the flow, the heart has four sets of valves. The heart is an amazing machine with a lot of moving parts—let this quiz game help you find your way around this most vital of organs.

The heart The heart is a unidirectional pump. Valves are present to prevent the backflow of blood. The right side pumps deoxygenated blood (low in oxygen and high in carbon dioxide) to the lungs. The left side pumps oxygenated blood (high in oxygen and low in carbon dioxide) to the organs of the body. • Deoxygenated blood enters the right atrium from the vena cava. • Blood moves into right ventricle. • Blood is pumped into the pulmonary artery. • The pulmonary artery carries deoxygenated blood to the lungs. • The blood becomes oxygenated in the lungs. • Oxygenated blood leaves the lung via the pulmonary vein. • Blood enters the left atrium. • Blood moves into the left ventricle. • Blood is pumped into the aorta, which carries oxygenated blood around the body. This unidirectional flow of blood through the heart shows that mammals have a double circulatory system. This means blood travels through the heart twice in one circulation of the body. Ventricular walls are thicker than atrial walls because the ventricles have to pump blood further. The left ventricle wall is thicker than the right because it pumps blood around the body while the right pumps blood to the lungs, located close to the heart. The following arteries and veins transport blood to and from some of the body’s organs: Blood vessel Function Vena cava Carries deoxygenated blood from the body back to the heart. Pulmonary artery Carries deoxygenated blood from the heart to the lungs. Pulmonary vein Carries oxygena...

The electrical system of the heart is critical to how it The movement of electrical signals across the heart is what is traced on an electrocardiogram (EKG). The EKG is also what allows irregularities in the heart's electrical system, and with them any related symptoms and medical conditions, to be assessed. This article explains five components of the cardiac conduction system and how they work. It also discusses how Where Do Electrical Impulses Start in the Heart? The heart generates its own electrical signal. This electrical signal is produced by a tiny structure known as the sinus node, located in the upper portion of the right atrium. The right atrium is one of four The cardiac electrical signal controls the heartbeat in two ways. First, since each electrical impulse generates one heartbeat, the number of electrical impulses determines the heart rate. In a normal sinus rhythm, that rate will be between 60 and 100 beats per minute. The sinus node signal also controls electrical conduction as it "spreads" across the heart. It causes the cells of the Illustration by Mira Norian for Verywell Health The components of the heart's electrical system, including the sinus node (SN) and atrioventricular node (AV node), are illustrated here. You can see the two atria and the two ventricles. Separating them is a layer of fibrous tissue, labeled the AV disc. This tissue keeps the electrical signal passing through the AV node. In this figure: • SN = sinus node • AVN = AV node • RA =...