Explain the difference between sequential and direct file access. A. Sequential access to data is used when the data has to be read from the start, in sequence. It is the norâ¦mal method of access for magnetic tape. Direct access is used when it is possible to jump directly to a file or data item without reading through all the items stored before it.
melanin (meËÂ·lÂ·nin), n a substance produced by melanocytes found in the deepest layer of the epidermis; protects the skin from the effects of the sun's harmful rays. Variations in skin color are a result of the level of melanin produced by each individual.
There are basically three layers to the skin, the epidermis on top, the dermis just below that, and below that is the hypodermis or subcutis layer. The epidermis is primarily made of dead skin cells that form a protective layer. It is also where the melanocytes, the color cells of the skin, are found.