Intercalculated Discs
so electrical impulses can be carried freely between cells
Cardiac impulses are carried to the myocardium via specialized muscle cells called Purkinje fibers. These fibers are part of the cardiac conduction system and help to transmit electrical signals rapidly and efficiently throughout the heart muscle.
Basically, the cardiac action potential travel across them, making it easier for the electrical impulses to move quickely.
An electrocardiogram (ECG or EKG) is the display or record of the electrical activity of the heart. It picks up electrical impulses generated by the polarization and depolarization of cardiac tissue and translates into a waveform.
Cardiac muscle is a type of involuntary striated muscle found in the walls of the heart, particularly the myocardium. Cardiac muscle cells are identified as cardiac myocytes or cardiomyocytes. Cardiac muscle is one of three major types of muscle, the others being skeletal and smooth muscle. Cardiac muscle, different from skeletal muscle, is composed of separate cellular elements. A cardiac muscle cell has a large nucleus and numerous mitochondria. The elevated concentration of mitochondria reveals the huge energy burden that predominant the heart. Contractile proteins of actin and myosin myofilaments are in the cytoplasm. They form bands of varying density. The heart produces regular electrical impulses causing the muscle myofibrils to glide above one another and squeeze the cardiac muscle. Some cardiac cells are self-excitable, contracting devoid of any signal from the nervous system. Each of these cells have their own inherent contraction rhythm. A section of the human heart called the sinoatrial node, or pacemaker, sets the rate and timing that all cardiac muscle cells contract. The SA node generates electrical impulses, from the SA node spreading rapidly through the walls of the artria, causing both artria to contract in unison. The impulses also pass to another section of specialized cardiac muscle tissue, a convey point called the atrioventricular node AV bundle or artioventricular bundle or Bundle or His. This collection of heart muscle cells are also specialized for electrical conduction that transmits the electrical impulses from the AV node to the point of the apex of the fascicular branches. The fascicular branches then lead to the Purkinje fibers then conduct the signals to the apex of the heart along and throughout the ventricular walls. The Purkinje fibers form conducting pathways called bundle branches.
Liver cells, also known as hepatocytes, are primarily involved in metabolism, detoxification, and storage of nutrients. Cardiac cells, found in the heart, are specialized for generating and conducting electrical impulses to regulate heart contractions. Additionally, cardiac cells have intercalated discs that allow for synchronized contraction of the heart muscle, while liver cells do not possess this feature.
A cardiac pacemaker uses electric impulses to regulate a beating heart. Cardiac pacemakers are designed to treat various forms of arrhythmia (heart beat irregularities).
The Sinoatrial (SA) node, also known as the pacemaker of the heart, is responsible for generating electrical impulses that initiate each cardiac cycle and determine the heart rate. It is located in the right atrium of the heart.
The "cardiac pacemaker," a group of cells in the sinoatrial node of the right atrium of the heart, which generate regular electrical impulses causing the heart to beat. The rate of contraction is regulated up or down by nerve fibers originating from elsewhere in the body.
Yes, an ECG records the electrical activity produced by the heart as it contracts and relaxes. This includes the electrical stimulation of the cardiac muscle by the conduction system, such as the SA node, AV node, and Purkinje fibers.
Cardiac muscle is considered autorhythmic, meaning it has the ability to generate its own electrical impulses without the need for external stimulation. This property allows the heart to beat independently of nerve input.
The cardiac rhythm is established by the sinoatrial (SA) node, which is the heart's natural pacemaker. The SA node generates electrical impulses that travel through the heart, coordinating the contraction and relaxation of the heart muscle to create a regular heartbeat.