Final answer:
The melanin responsible for red to yellow hair color is called pheomelanin. It is one of the two main types of melanin, the other being eumelanin, which causes darker hair colors. Pheomelanin is produced by melanocytes in the hair papilla and is influenced by genetic factors.
Step-by-step explanation:
The melanin found in hair that gives it a red to yellow color is known as pheomelanin. Unlike eumelanin, which is the melanin that provides brown and black pigment, pheomelanin is responsible for the lighter shades of hair ranging from red to blonde. Melanin is produced by cells called melanocytes, which are located in the hair papilla. The amount and type of melanin determine the color of the hair, which is a genetically determined trait.
Exposure to UV rays from the sun stimulates the production of melanin in the skin, resulting in a tan. The increased melanin helps protect the DNA in epidermal cells from UV ray damage. This balance of melanin production is important for protecting the skin while also allowing for the production of vitamin D.