The color of the skin is primarily affected by the amount of blood it contains and what other factor?

The color of the skin is primarily influenced by the amount of melanin present. Melanin is a pigment produced by specialized cells called melanocytes, and its presence determines the shade of skin. Individuals with higher concentrations of melanin typically have darker skin, while those with less melanin have lighter skin. The amount of blood in the skin can also affect skin tone temporarily, such as during physical exertion or blushing, but it is the melanin that provides the baseline color of the skin.

Keratin, while important for skin health and resilience, does not play a direct role in determining skin color. Collagen contributes to skin structure and elasticity but is not related to the pigmentation. Cholesterol is essential for various bodily functions, but it does not influence the skin's color.