Anatomical terms of muscle This may be a bone, a tendon or the subcutaneous dermal connective tissue. Insertions are usually connections of muscle via tendon to bone. The insertion is a bone that tends to be distal, have less mass, and greater motion than the origin during a contraction. Muscles may also be described by the direction that the muscle fibres run in. Hypertrophy is increase in muscle size from an increase in size of individual muscle cells. This usually occurs as a result of exercise. Anatomical terms of muscle Muscles are described using unique anatomical terminology according to their actions and structure. There
Muscle network which could show a large degree of divergence in the formation of muscle cells. Through this analysis, it seems that the myogenic GRN is an ancestral GRN with actual changes in myogenic function and structure possibly being linked to later coopts of genes at different times and places. Evolutionarily, specialized forms of skeletal and cardiac muscles predated the divergence of the vertebrate/arthropod evolutionary line. This indicates that these types of muscle developed in a common ancestor sometime before 700 million years ago (mya). Vertebrate smooth muscle was found to have evolved independently from the skeletal and cardiac muscle types.