Anatomy And Physiology
Compare and contrast the characteristics of skeletal muscle, smooth muscle, and cardiac muscle
Sample Solution
Here's a breakdown of the key characteristics comparing skeletal, smooth, and cardiac muscle:
| Feature | Skeletal Muscle | Smooth Muscle | Cardiac Muscle |
|---|---|---|---|
| Location | Attached to bones | Walls of organs, blood vessels | Heart only |
| Control | Voluntary | Involuntary | Involuntary |
| Appearance under microscope | Striated (banded) | Spindle-shaped, no striations | Striated (banded) |
| Cells | Multinucleated, long, cylindrical | Single nucleus, spindle-shaped | Single nucleus, branched |
| Contraction speed | Fast | Slow, sustained | Moderate |
| Fatigue resistance | Low | High | High |
| Function | Movement of the body | Movement of substances through organs, blood vessel regulation | Pumping blood throughout body |
Full Answer Section
Similarities:- All three muscle types are capable of contraction, which is the shortening of muscle fibers to generate force.
- All three types use actin and myosin proteins to create this contractile force.
- Control:Skeletal muscle is voluntary, meaning we can consciously control its movement. Smooth and cardiac muscles are involuntary, meaning their contractions are not under conscious control.
- Structure:Skeletal and cardiac muscles have a striated appearance due to the organized arrangement of actin and myosin filaments. Smooth muscle lacks this striation.
- Cells:Skeletal muscle cells are multinucleated and long, while smooth muscle cells have a single nucleus and a spindle shape. Cardiac muscle cells are also single-nucleated, but branched and interconnected.
- Contraction:Skeletal muscle contracts quickly and powerfully but fatigues easily. Smooth muscle contracts slowly and sustainedly with high fatigue resistance. Cardiac muscle has a moderate contraction speed and high fatigue resistance.
- Location and Function:Skeletal muscle is responsible for gross body movements. Smooth muscle is found in various organs and regulates the movement of substances within them. Cardiac muscle is unique to the heart and pumps blood throughout the body.