DEFINITION of 'Commercial'. Relating to commerce. In the investment field, the term commercial is generally used to refer to a trading entity engaged in business activities that are hedged by positions in the futures or options markets.
The melanocortin 1 receptor controls which type of melanin is produced by melanocytes. When the receptor is activated, it triggers a series of chemical reactions inside melanocytes that stimulate these cells to make eumelanin. If the receptor is not activated or is blocked, melanocytes make pheomelanin instead of eumelanin.
Melanin is produced by cells called melanocytes in a process called melanogenesis. Melanin is made within small membraneâbound packages called melanosomes. As they become full of melanin, they move into the slender arms of melanocytes, from where they are transferred to the keratinocytes.elanin is produced by cells called melanocytes in a process called melanogenesis. Melanin is made within small membraneâbound packages called melanosomes. As they become full of melanin, they move into the slender arms of melanocytes, from where they are transferred to the keratinocytes.