In my critical anatomy lesson, I disputed skeletal muscle tissue, which is among the three types of muscle tissue discovered in the person body, together with cardiac and also smooth muscle tissue. In this article and video, i’m going to talk about cardiac muscle tissue.

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Of the three varieties of muscle tissue, cardiac muscle tissue is the one that’s near and dear to my heart because, well, it’s in my heart! In fact, it is the only ar you’ll discover cardiac muscle tissue, and also the an extremely word “cardiac” literally means “relating come the heart.”

The cells that comprise cardiac muscle are called cardiomyocytes (or cardiocytes), and together, they make up the myocardium, the muscle class of the heart. This muscle layer causes the love to contract in a wringing motion, i beg your pardon pumps blood throughout the body, offering organs and tissues through oxygen and vital nutrients.

Cardiac muscle shares some similarities come skeletal muscle tissue, but there are additionally some vital differences. First, stop talk around the similarities.

Similarities of Cardiac and Skeletal Muscle Tissue

Cardiac Muscle Connective Tissue

Like skeletal muscle, cardiac muscle cells are surrounded and also separated by a connective tissue layer dubbed endomysium. Remember, “endo” method within, and also “mysium” method muscle, therefore this is the connective tissue “within” or “closest to” the actual muscle cells or fibers.

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Cardiac Muscle convulsion Mechanism

Cardiac muscle also contains myofibrils and also sarcomeres, which not only allow contraction, but they also create the striations (striped pattern) that characterize both cardiac and skeletal muscle tissue. And that’s something you’ll want to remember: Both skeletal and cardiac muscle tissue have striations (or stripes)!

As I discussed in my skeletal muscle video, sarcomeres save actin and myosin filaments that slide during contraction, and also the details arrangement of these filaments into zones and also bands creates the striped (or striated) appearance.

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Differences of Cardiac vs skeleton Muscle

Even despite skeletal muscle and also cardiac muscle have similarities, there are vital differences between them.

Cardiac Muscle contraction Control

Whereas skeleton muscle contract on a voluntary basis (when girlfriend consciously desire it come contract), cardiac muscle contracts on an INVOLUNTARY communication (without your mindful control) via the autonomic concerned system. That’s a an excellent thing, because let’s be honest: if we had actually to consciously mental to make our heart pump, most of us would most likely be dead by now.

Cardiac Muscle Shape

There is also a distinction in shape between these muscle types. Skeleton muscle tissue creates into long, cylindrical fibers, yet cardiac muscle tissue is developed into solitary cells that have an rarely often rare branched appearance. These individual cells sign up with to various other cardiac cell via intercalated discs, i m sorry I’ll talk about in a moment.

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Cardiac Muscle Nuclei

Another difference is the skeletal muscle has multiple nuclei that room scattered around the peripheral section of the muscle cells, whereas cardiac muscle includes only 1-2 nuclei, which are located near the center of the cell.

Intercalated Discs in Cardiac Muscle

Finally, crucial characteristic that cardiac muscle cells the you’ll desire to psychic is the they room joined together by something referred to as intercalated discs, i m sorry are lacking in bones muscle tissue.

These intercalated discs type an interlocking zigzag connection in between the individual cardiac muscle cells, and they consists three species of cabinet junctions: desmosomes, fasciae adherens, and gap junctions.

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Desmosomes act as binders throughout contraction, sustaining the filaments in adjoining cardiac cells to stop separation.Fasciae adherens additionally work to connect and also bind cardiac muscle cell by adhering come the actin filaments.Gap junctions space the tiny channels in between adjoining cardiac cells that enable for the rapid passage of ion from when cell come the next, leading to depolarization and also contraction, which reasons cardiac muscle cells to contract simultaneously. Specialized pacemaker cell in the heart attach to these gap junctions and also work to manage the love rate.

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Free Quiz and more Anatomy Videos

Take a totally free cardiac muscle anatomy quiz come test your knowledge, or review our cardiac muscle video. In addition, you might want to clock our anatomy and physiology lectures ~ above YouTube, or check our anatomy and also physiology notes.