Difference between Skeletal, Smooth and Cardiac Muscles
By Theydiffer - July 6, 2015

Your body is made up of many muscles, each of which is found in a particular part of your body and has a distinct function. If you are a sportsman or are feeling unwell, understanding how your body works can be helpful in staying fit or avoiding injury. Since muscles are involved in important functions of the body such as walking, blood flow, and food digestion, among others, it is important to understand how they work.


Cardiac muscle

Cardiac muscles are striated and branched muscles, resembling a Y shape, found on the heart’s walls. Their cells have centrally located nuclei and are attached to each other by intercalated discs (thick plasma membranes). Cardiac muscles are involuntarily controlled and their main function is to pump blood through the heart. These muscles cannot be fatigued because they their cells have the highest amount of mitochondria nuclei in the body.

Comparison Chart

Skeletal MuscleSmooth MuscleCardiac Muscle
StriatedNot striatedStriated
Voluntarily controlledInvoluntarily controlledInvoluntarily controlled
Cells have many nuclei that are peripheral to their fibersCells have only one nucleus at the centerCells have only one nucleus at the center
Attached to bonesFound on hollow internal organs such as stomach and blood vesselsFound on the heart’s wall
Responsible for movement of the skeleton and musclesResponsible for the movement of substances such as food and bloodResponsible for moving blood in the heart

Skeletal vs Smooth vs Cardiac Muscle

What is the difference between skeletal, smooth, and cardiac muscles? The difference lies in the location of nuclei in their cells, the function for each muscle, whether they are voluntarily controlled or not, and their location on the body.

Unlike the smooth muscles that are not striated and smooth, the skeletal and cardiac muscles have a complex and repetitive arrangement of sacromeres, i.e. myofilaments made of actin and myosin that are stacked together and overlap in a regular but repeating pattern along these muscles. The skeletal muscles are responsible for movements of the skeleton such as walking and moving arms. They also control facial tissues responsible for activities such as smiling or frowning. The cardiac muscle controls blood flow in the heart, while the smooth muscles move food and other substances along the gastrointestinal system.

Of the three sets of muscles, the skeletal muscles are the only ones that are consciously controlled by the brain. This is because skeletally controlled movements such as walking are only necessary at times. The other two, smooth and cardiac muscles, are involuntarily controlled to perform their respective functions such as blood flow which is needed all the time and is in fact vital for survival.