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Does cardiac muscle have desmosomes and gap junctions?

Does cardiac muscle have desmosomes and gap junctions?

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 there gap junctions in cardiac muscle?

In the heart, cardiac muscle cells (myocytes) are connected end to end by structures known as intercalated disks. Adjacent to the intercalated discs are the gap junctions, which allow action potentials to directly spread from one myocyte to the next.

Why do heart cells need both gap junctions and desmosomes?

Intercalated discs are part of the sarcolemma and contain two structures important in cardiac muscle contraction: gap junctions and desmosomes. This joining is called electric coupling, and in cardiac muscle it allows the quick transmission of action potentials and the coordinated contraction of the entire heart.

What are tight junctions desmosomes and gap junctions?

Plasmodesmata are channels between adjacent plant cells, while gap junctions are channels between adjacent animal cells. A tight junction is a watertight seal between two adjacent cells, while a desmosome acts like a spot weld.

Does cardiac muscle have sarcomeres?

Although cardiac myocytes are striated with sarcomeres of very similar composition to those of skeletal muscle, there are important structural and functional differences between the two muscle types.

What muscle cells have desmosomes and gap junctions?

Cardiac muscle cells are rectangular shaped cells connected by regions called intercalated discs. Intercalated discs contain gap junctions and desmosomes.

What is the physiological significance of gap junctions in cardiac myocytes?

Gap junctions are membrane channels that mediate the cell-to-cell movement of ions and small metabolites. In the heart, gap junctions play an important role in impulse conduction.

Where are tight junctions and desmosomes?

Tight junctions (blue dots) between cells are connected areas of the plasma membrane that stitch cells together. Adherens junctions (red dots) join the actin filaments of neighboring cells together. Desmosomes are even stronger connections that join the intermediate filaments of neighboring cells.

Where are myocytes found and where are cardiomyocytes found?

Also known as myocardiocytes, cardiomyocytes are cells that make up the heart muscle/cardiac muscle. As the chief cell type of the heart, cardiac cells are primarily involved in the contractile function of the heart that enables the pumping of blood around the body.