MICROANATOMY

Detailed explanation-1: -A myofibril is composed of many sarcomeres running along its length; thus, myofibrils and muscle cells contract as the sarcomeres contract.

Detailed explanation-2: -Contraction of smooth muscle is initiated by a Ca2+-mediated change in the thick filaments, whereas in striated muscle Ca2+ mediates contraction by changes in the thin filaments.

Detailed explanation-3: -Skeletal muscles are involved in contraction and relaxation. An action potential travels through the motor neuron. The motor neurons are linked to the muscle fibers at the neuromuscular junction. When this nervous signal reaches the neuromuscular junction the neurotransmitter called acetylcholine is released.

Detailed explanation-4: -Contractility is due to the presence of myofibrils in the muscle fiber cytoplasm, as large cellular assemblies. Also, myofibers are responsible for the force that the muscle generates which represents a countless aspect of human life.

Detailed explanation-5: -Tissue responsible for the movement in our body is muscular tissue. This is comprised of thin cylindrical muscular fibers. These fibers contract to move the part of the body and lengthen or comes to its original shape when the part is relaxed.