What cell is responsible for skin pigmentation?
A. Langerhans
B. Keratinocyte
c. Melanocyte
D. Merkel’s
The correct answer and explanation is:
The correct answer is C. Melanocyte.
Explanation:
Skin pigmentation is primarily determined by melanocytes, specialized cells found in the epidermis, particularly in the basal layer. These cells are responsible for producing melanin, a pigment that gives skin its color. Melanin comes in two main forms: eumelanin (which is brown or black) and pheomelanin (which is yellow or red). The amount and type of melanin produced by melanocytes determine the color of an individual’s skin, hair, and eyes.
Melanocytes synthesize melanin through a process known as melanogenesis. The precursor molecule, tyrosine, is converted into melanin through a series of enzymatic reactions. Once melanin is produced, it is stored in organelles called melanosomes. The melanosomes are then transferred to surrounding keratinocytes, the predominant cell type in the epidermis, which help distribute the pigment throughout the skin.
The production of melanin is influenced by several factors, including genetics, UV radiation, and hormonal changes. For example, exposure to ultraviolet (UV) light stimulates melanocytes to produce more melanin as a protective response to the damaging effects of UV radiation. This is why individuals who spend time in the sun often develop a tan, as melanocytes increase melanin production.
Other cells mentioned in the options, such as Langerhans cells and Merkel cells, play different roles in the skin. Langerhans cells are involved in immune responses, while Merkel cells are associated with tactile sensation and pressure perception.
Overall, melanocytes are crucial for skin pigmentation and provide a protective function against UV radiation by absorbing and dispersing melanin.