Skeletal muscle fibets are striated and each acts _of the neighboring muscle fibers
Skeletal muscle fibers are striated and each acts independently of the neighboring muscle fibers.
To understand why skeletal muscle fibers act independently, we need to look at the organization of skeletal muscles.
Skeletal muscles are composed of many muscle fibers, also known as myofibers, which are bundled together by connective tissue. Each individual muscle fiber is surrounded by a layer of connective tissue called endomysium. Multiple muscle fibers are grouped together into bundles called fascicles, which are wrapped in another layer of connective tissue called perimysium. Finally, the entire muscle is enclosed by a layer of connective tissue called epimysium.
Within each muscle fiber, there are smaller units called myofibrils, which are responsible for the muscle's contractile properties. Myofibrils contain repeating units called sarcomeres, which are the functional units of muscle contraction. Sarcomeres are made up of thick and thin filaments, which give skeletal muscles their striated appearance.
Importantly, each muscle fiber is innervated by a motor neuron, which stimulates muscle contraction. The motor neuron releases neurotransmitters at the neuromuscular junction, which signal the muscle fiber to contract.
When a muscle contracts, the sarcomeres within each individual muscle fiber shorten, causing the entire muscle fiber to contract. Since each muscle fiber is innervated by a separate motor neuron, the contraction of one muscle fiber is not dependent on the contraction of its neighboring fibers. This allows for precise control and coordination of muscle movement, as each muscle fiber can be activated independently of its neighbors.
In summary, skeletal muscle fibers are striated and act independently of their neighboring muscle fibers. This independent action is due to the innervation of each muscle fiber by a separate motor neuron, allowing for precise control and coordination of muscle movement.