Voluntary Muscle Tissue
Voluntary muscle tissue, also known as skeletal muscle tissue, is one of the three types of muscle tissue found within the human body. It is called “voluntary” because we have control over its movement and can consciously choose to contract or relax it. This type of muscle tissue is responsible for various movements and activities such as walking, talking, and picking up objects.
The cells that make up voluntary muscle tissue are long, cylindrical, and multi-nucleated. Each cell is known as a muscle fiber and is composed of smaller units called myofibrils. These myofibrils contain sarcomeres, which are responsible for muscle contraction. The overall structure of voluntary muscle tissue allows for coordinated movement and precise control over our body’s actions.
Voluntary muscle tissue is attached to bones via tendons, and these muscles work in pairs to create movement. For example, when you lift your arm, one muscle contracts while the opposite muscle relaxes, allowing for smooth and controlled movements. These muscle fibers can be voluntarily stimulated by electrical impulses from the brain, which initiate the contraction and relaxation of muscle cells.
Involuntary Muscle Tissue
Involuntary muscle tissue, also known as smooth muscle tissue, is another type of muscle tissue found in the human body. Unlike voluntary muscle tissue, involuntary muscle tissue is not under conscious control, meaning that we cannot directly control its movement. This type of muscle tissue is responsible for the movement of internal organs, such as the digestive tract, blood vessels, and respiratory system.
The cells of involuntary muscle tissue are spindle-shaped and have a single nucleus. They are arranged in layers that allow for coordinated contractions and relaxation, ensuring the proper functioning of the organs they are found in. Involuntary muscle tissue is regulated by the autonomic nervous system, which controls and coordinates involuntary actions in the body.
While we may not be able to directly control involuntary muscle tissue, its contraction and relaxation are vital for maintaining essential bodily functions. For example, the smooth muscle tissue in our digestive system helps push food along the digestive tract, while the smooth muscle tissue in our blood vessels helps regulate blood pressure.
Differences in Function
The main difference between voluntary and involuntary muscle tissue lies in their respective functions and control. As mentioned earlier, voluntary muscle tissue allows for conscious control over movement, enabling us to perform various physical activities. In contrast, involuntary muscle tissue is not under conscious control and is responsible for the automatic movement and functions of our internal organs.
Another difference is the way in which these muscles are activated. Voluntary muscle tissue can be voluntarily stimulated by electrical impulses from the brain, while involuntary muscle tissue is regulated by the autonomic nervous system. This means that voluntary muscle tissue can be selectively activated or relaxed based on our conscious decisions, while involuntary muscle tissue functions automatically without our direct control.
Differences in Structure
The structure of voluntary and involuntary muscle tissue also varies. Voluntary muscle tissue is composed of long, cylindrical, multi-nucleated cells called muscle fibers. These fibers are organized into bundles and are attached to bones via tendons. Involuntary muscle tissue, on the other hand, consists of spindle-shaped cells with a single nucleus. These cells are arranged in layers and are found in the walls of organs.
Additionally, the presence of sarcomeres, the structural unit responsible for muscle contraction, differs between voluntary and involuntary muscle tissue. Sarcomeres are abundant in voluntary muscle tissue, allowing for precise control over muscle movements. In contrast, involuntary muscle tissue has fewer sarcomeres, resulting in slower and less coordinated contractions.
Summary
In summary, voluntary muscle tissue, also known as skeletal muscle tissue, is under conscious control and responsible for movements that we can control, such as walking and talking. In contrast, involuntary muscle tissue, also known as smooth muscle tissue, is not under conscious control and is responsible for the automatic movement of our internal organs. The structure and activation of these muscle tissues differ, with voluntary muscle tissue being composed of multi-nucleated cells with abundant sarcomeres and involuntary muscle tissue consisting of spindle-shaped cells with fewer sarcomeres.
