What is the primary function of nails in relation to fingers and toes?

The primary function of nails is to provide protection and cover the distal phalanges, which are the bones at the tips of the fingers and toes. Nails act as a hard outer layer that guards these sensitive areas against injuries and environmental factors such as dirt and pathogens. This protective feature is particularly important because the fingertips are highly sensitive, and the nails help shield the underlying tissues, including skin and nerves.

While nails can also contribute to gripping by providing a solid surface for the pads of fingers, their primary role is protective in nature. They do not produce heat for the extremities, nor do they play a significant role in sensory information collection. Therefore, the function centered around protection accurately captures the essential purpose of nails in relation to fingers and toes.