What are tiny grains of pigment deposited into cells in the epidermis called?

Tiny grains of pigment deposited into cells in the epidermis are referred to as melanin. Melanin is produced by specialized cells known as melanocytes, which are located in the basal layer of the epidermis. This pigment is responsible for the color of the skin, hair, and eyes, and it plays a crucial role in protecting the skin from the harmful effects of ultraviolet (UV) radiation by absorbing and dissipating UV rays.

Carotene, while it is a pigment that contributes to the color of skin and is found in the outermost layers of the stratum corneum, is not primarily deposited within the cells of the epidermis like melanin. Hemoglobin is the protein found in red blood cells that carries oxygen and gives blood its red color; it is not a pigment deposited in the skin. Cholesterol is a type of fat molecule that plays several roles in the body, including serving as a building block for cell membranes, but it is not involved in pigmentation. Thus, melanin is the accurate answer as it is specifically associated with the pigmentation found in the epidermis.