a domain specific word like tectonic has both literal and figurative meanings but for the most part the use of the word is found in geology and physics as you may recall earthquakes and tsunamis can be caused by tectonic shifts in which two landmasses collide
Epidermis: It is the superficial avascular layer of stratified squamous epithelium, It is ectodermal in origin and gives rise to the appendages of the skin, namely hair, nails, sweat glands and sebaceous glands.Structurally the epidermis is made up of a superficial cornified zone and a deep germinative zone.ermis: Dermis or corium is the deep, vascular layer of the skin derived from mesoderm. It is made up of connective tissue mixed with blood vessels, lymphatics and nerves. The connective tissue is arranged into a superficial papillary layer and a deep reticular layer.
In this article. Avascular necrosis (AVN), also called osteonecrosis, aseptic necrosis, or ischemic bone necrosis, is a condition that occurs when there is loss of blood to the bone. Because bone is living tissue that requires blood, an interruption to the blood supply causes bone to die. If not stopped, this process eventually causes the bone to collapse. Avascular necrosis most commonly occurs in the upper leg. Other common sites are the upper arm, knees, shoulder, and ankles.