Muscle cell

A muscle cell, also known as a myocyte, is a type of cell that makes up muscle tissue. There are three types of muscle cells in the human body: skeletal, cardiac, and smooth muscle cells. Each type has a unique structure and function.

Structure

Muscle cells are elongated and are packed with myofibrils, which are bundles of protein filaments that play a key role in muscle contraction. The cell's cytoplasm, known as the sarcoplasm, contains numerous mitochondria to meet the energy demands of the cell.

Skeletal muscle cells

Skeletal muscle cells, also known as muscle fibers, are long, cylindrical cells that contain multiple nuclei. They are surrounded by a plasma membrane called the sarcolemma, which helps transmit signals from the nervous system.

Cardiac muscle cells

Cardiac muscle cells, or cardiomyocytes, are shorter and branched, with one or two centrally located nuclei. They are connected by intercalated discs, which allow electrical signals to pass between cells, coordinating their contraction.

Smooth muscle cells

Smooth muscle cells are spindle-shaped and contain a single nucleus. Unlike skeletal and cardiac muscle cells, they do not have striations.

Function

Muscle cells are responsible for producing force and motion. They do this by contracting in response to electrical signals from the nervous system.

Skeletal muscle cells

Skeletal muscle cells contract to move the bones of the skeleton. They are under voluntary control, meaning we can consciously control their contraction.

Cardiac muscle cells

Cardiac muscle cells contract to pump blood throughout the body. They are under involuntary control, meaning their contraction is not consciously controlled.

Smooth muscle cells

Smooth muscle cells contract to move substances through the body's organs, such as food through the digestive tract or blood through the blood vessels. They are also under involuntary control.

See also

• Muscle tissue
• Muscle contraction
• Myofibril
• Sarcoplasm
• Mitochondria
• Sarcolemma
• Intercalated disc

Muscle_cell

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  Synapse diagram
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  Skeletal muscle diagram
• Sliding filament mechanism diagram
  Sliding filament mechanism diagram