Do cardiac muscle tissue have intercalated discs?
Cardiac muscle is striated, like skeletal muscle, as the actin and myosin are arranged in sarcomeres, just as in skeletal muscle. However, cardiac muscle is involuntary. Cardiac muscle cells usually have a single (central) nucleus. The densely staining regions at the ends of the muscle fibres are intercalated discs.
What type of muscle tissue is cardiac muscle?
striated muscle tissue
Cardiac muscle is an involuntary striated muscle tissue found only in the heart and is responsible for the ability of the heart to pump blood.
What are intercalated discs found in cardiac muscle cells?
Intercalated discs are part of the sarcolemma and contain two structures important in cardiac muscle contraction: gap junctions and desmosomes. A gap junction forms channels between adjacent cardiac muscle fibers that allow the depolarizing current produced by cations to flow from one cardiac muscle cell to the next.
Why do cardiac muscles have intercalated discs?
Cardiac muscle fibers cells also are extensively branched and are connected to one another at their ends by intercalated discs. An intercalated disc allows the cardiac muscle cells to contract in a wave-like pattern so that the heart can work as a pump.
What are the junctions between cardiac muscle cells?
Cardiac muscle cells are equipped with three distinct types of intercellular junction–gap junctions, “spot” desmosomes, and “sheet” desmosomes (or fasciae adherentes)–located in a specialized portion of the plasma membrane, the intercalated disk.
Are cardiac muscles cylindrical?
Cardiac muscles are branched and cylindrical in shape. They are uninucleate cells.
Which muscle tissue contains Myofilaments?
myofilaments are composed of the contractile proteins actin and myosin. In striated muscle, the myofilaments are arranged into sacromeres, the smallest contractile unit in striated muscle. A myofibril is an organelle within a muscle cell made up of repeating sacromeres.
What is the cardiac muscle of the heart?
Cardiac muscle tissue, or myocardium, is a specialized type of muscle tissue that forms the heart. This muscle tissue, which contracts and releases involuntarily, is responsible for keeping the heart pumping blood around the body.
Where is cardiac muscle tissue found?
the heart
Cardiac muscle cells are located in the walls of the heart, appear striped (striated), and are under involuntary control. Smooth muscle fibers are located in walls of hollow visceral organs (such as the liver, pancreas, and intestines), except the heart, appear spindle-shaped, and are also under involuntary control.
What types of tissues make up the cardiac conduction system?
This group of muscle cells is called the cardiac conduction system. The main parts of the system are the SA node, AV node, bundle of HIS, bundle branches, and Purkinje fibers. Let’s follow a signal through the contraction process. The SA node starts the sequence by causing the atrial muscles to contract.
What is skeletal muscle tissue?
Skeletal muscle tissue is composed of long cells called muscle fibers that have a striated appearance. Muscle fibers are organized into bundles supplied by blood vessels and innervated by motor neurons.