dÃ©jÃ  vu [(day-zhah vooh)] The strange sensation that something one is now experiencing has happened before: âI knew I had never been in the house before, but as I walked up the staircase, I got a weird sense of dÃ©jÃ  vu.â From French, meaning âalready seen.â.
Muscle is a soft tissue found in most animals. Muscle cells contain protein filaments of actin and myosin that slide past one another, producing a contraction that changes both the length and the shape of the cell.uscle tissues are derived from the mesodermal layer of embryonic germ cells in a process known as myogenesis. There are three types of muscle, skeletal or striated, cardiac, and smooth.
The muscles of the back can be divided into three groups â superficial, intermediate and intrinsic: 1  Superficial â associated with movements of the shoulder. 2  Intermediate â associated with movements of the thoracic cage. 3  Deep â associated with movements of the vertebral column.