17.3: Cardiac Muscle - Medicine LibreTexts
2022年7月27日 · Figure \(\PageIndex{1}\): Cardiac Muscle. (a) Cardiac muscle cells have myofibrils composed of myofilaments arranged in sarcomeres, T tubules to transmit the impulse from the sarcolemma to the interior of the cell, numerous mitochondria for energy, and intercalated discs that are found at the junction of different cardiac muscle cells.
17.3A: Mechanism and Contraction Events of Cardiac Muscle Fibers
Cardiac muscle fibers contract via excitation-contraction coupling, using a mechanism unique to cardiac muscle called calcium -induced calcium release. Excitation-contraction coupling describes the process of converting an electrical stimulus ( action potential ) into a mechanical response (muscle contraction).
10.8: Cardiac Muscle Tissue - Medicine LibreTexts
2023年2月24日 · Similar to skeletal muscle, cardiac muscle is striated and organized into sarcomeres, possessing the same banding organization as skeletal muscle (Figure \(\PageIndex{1}\) ). However, cardiac muscle fibers are shorter than skeletal muscle fibers and usually contain only one nucleus, which is located in the central region of the cell.
17.3: Cardiac Muscle and Electrical Activity - Medicine LibreTexts
Recall that cardiac muscle shares a few characteristics with both skeletal muscle and smooth muscle, but it has some unique properties of its own. Not the least of these exceptional properties is its ability to initiate an electrical potential at a fixed rate that spreads rapidly from cell to cell to trigger the contractile mechanism.
17.3: Cardiac Muscle and Electrical Activity
2024年10月20日 · Compared to the giant cylinders of skeletal muscle, cardiac muscle cells, or cardiomyocytes, are considerably shorter with much smaller diameters. Cardiac muscle also demonstrates striations, the alternating pattern of dark A bands and light I bands attributed to the precise arrangement of the myofilaments and fibrils that are organized in ...
3.4: Distinguishing Between The Three Types of Muscle Tissue
One cardiac muscle fiber is the material between two intercalated discs. Cardiac muscle fibers are mononucleate , with only one nucleus per fiber, and they can sometimes be branched . Smooth muscle is found in the walls of internal organs, such as the organs of the digestive tract, blood vessels, and others.
19.2: Cardiac Muscle and Electrical Activity - Medicine LibreTexts
2022年5月13日 · Figure \(\PageIndex{1}\): Cardiac Muscle. (a) Cardiac muscle cells have myofibrils composed of myofilaments arranged in sarcomeres, T tubules to transmit the impulse from the sarcolemma to the interior of the cell, numerous mitochondria for energy, and intercalated discs that are found at the junction of different cardiac muscle cells.
3.5: Muscle Tissue - Medicine LibreTexts
2024年9月15日 · The cardiac muscle pumps blood through the body and is under involuntary control. The attachment junctions hold adjacent cells together across the dynamic pressures changes of the cardiac cycle. Smooth muscle tissue contraction is responsible for involuntary movements in the internal organs. It forms the contractile component of the digestive ...
9.1A: Structure and Function of the Muscular System
Cardiac Muscle Tissue. Cardiac muscle tissue is found only in the heart, where cardiac contractions pump blood throughout the body and maintain blood pressure. As with skeletal muscle, cardiac muscle is striated; however it is not consciously controlled and …
17.1C: Layers of the Heart Walls - Medicine LibreTexts
The myocardium is the muscle tissue of the heart, composed of cardiac muscle cells called cardiomyocytes that receive nervous stimulation from the sinoatrial (SA) and atrioventricular (AV nodes via the Purkinje fibers. Cardiomyocytes are shorter than skeletal myocytes, and contain fewer nuclei. Cardiac muscle is striated.
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