Cells are specialized in their anatomy and physiology to perform different tasks. All cells exhibit a voltage difference across the cell membrane. Nerve cells and muscle cells are excitable. Their cell membrane can produce electrochemical impulses and conduct them along the membrane.In muscle cells, this electric phenomenon is also associated with the contraction of the cell.2) numerous short processes of the soma, called the dendrites; and, (3) the single long nerve fiber, the axon. These are described in Figure 2.1. The body of a nerve cell (see also (Schad and Ford, 1973)) is similar to that of all other cells.
Blood leaks into tissues under the skin and causes the black-and-blue color. As bruises (contusions) heal, usually within 2 to 4 weeks, they often turn colors, including purplish black, reddish blue, or yellowish green. Sometimes the area of the bruise spreads down the body in the direction of gravity. A bruise on a leg usually will take longer to heal than a bruise on the face or arms. Most bruises are not a cause for concern and will go away on their own. Home treatment may speed healing and relieve the swelling and soreness that often accompany bruises that are caused by injury.
Once a patient returns home, itâs normal to experience swelling and bruising that increases for the first few days and then begins to fade over the next few weeks. In most cases, individuals can return to work and normal activity after one to two weeks. If significant bruising remains, you are welcome to wear makeup to help cover these effects. The degree of swelling and bruising will depend on the technique used and your unique anatomical factors. Numbness in the treated area is also normal, and sensation should return gradually.