Muscle Types

What are the similarities and differences between Skeletal Muscle, Cardiac Muscle and Smooth Muscle?

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...This muscle type is only found within the heart. It is under un-conscious control. Interestingly, some martial artists have made claims that they have maintained conscious control in deep meditation and while controversial, in certain reported cases this claim was actually verified by professionals. Cardiac muscle cells have a single oval nucleus. Each cell is approximately ~20 µm in diameter and ~100 µm in length much smaller than skeletal muscle. Cardiac muscle fibers form long chains of cells that branch and interlace. Cardiac muscle is striated like skeletal muscle. The T-tubules in cardiac muscle do not have triads like in skeletal muscle nor do they have terminal cisternae in the SR. Cardiac muscle cells rely on aerobic metabolism and therefore store the necessary oxygen in reserves of myoglobin, have reserves of glycogen and lipid inclusions, and many mitochondria.
An intercalated disc is a junction of one cell with another in a particular chain and they can be seen as a dark line. The intercalated disc is likely the most important feature of the heart because it allows the muscle to contract as a whole. Action potentials can travel across an intercalated disc rapidly moving from one cell to another. The myofibrils of these cells anchor themselves in the disc and allow many cells to contract in unison (functional synctium).
Cardiac muscle does not need neuronal stimulation to contract. The contractility is maintained by pacemaker cells that periodically ...