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In a healthy heart all activities and rests during each individual cardiac cycle, or heartbeat, are initiated and orchestrated by signals of the heart's electrical conduction system, which is the "wiring" of the heart that carries electrical impulses throughout the body of cardiomyocytes, the specialized muscle cells of the heart.
The heart tube continues stretching and by day 23, in a process called morphogenesis, cardiac looping begins. The cephalic portion curves in a frontal clockwise direction. The atrial portion starts moving in a cephalically and then moves to the left from its original position. This curved shape approaches the heart and finishes its growth on ...
The left ventricle is longer and more conical in shape than the right, and on transverse section its concavity presents an oval or nearly circular outline. It forms a small part of the sternocostal surface and a considerable part of the diaphragmatic surface of the heart; it also forms the apex of the heart.
The heart is the first functional organ to develop and starts to beat and pump blood at about three weeks into embryogenesis. This early start is crucial for subsequent embryonic and prenatal development. The heart derives from splanchnopleuric mesenchyme in the neural plate which forms the cardiogenic region.
The heart is a muscular organ situated in the mediastinum.It consists of four chambers, four valves, two main arteries (the coronary arteries), and the conduction system. The left and right sides of the heart have different functions: the right side receives de-oxygenated blood through the superior and inferior venae cavae and pumps blood to the lungs through the pulmonary artery, and the left ...
Boo to You Ghost Pumpkin. A tall, narrow pumpkin is the proper setting for this friendly ghost. Using the pattern, start with the eyes and mouth, then carve inside the letters B-O-O. Remove the ...
The earliest heart-shaped charges in heraldry appear in the 12th century; the hearts in the coat of arms of Denmark go back to the royal banner of the kings of Denmark, in turn based on a seal used as early as the 1190s. However, while the charges are clearly heart-shaped, they did not depict hearts in origin, or symbolize any idea related to love.