What is the primary function of the integumentary system?

The primary function of the integumentary system is to protect the body from fluid loss, injury, and infection. This system is composed primarily of the skin, along with associated structures like hair, nails, glands, and sensory receptors. The skin acts as a barrier that helps prevent the entry of pathogens and external harm while also minimizing water loss from internal tissues.

This protective function is critical for maintaining overall health, as it helps to shield the body from environmental hazards, including bacteria, viruses, and harmful substances. Additionally, the integumentary system plays a role in regulating body temperature and synthesizing vitamin D, but its fundamental role remains centered on protection.

The other options relate to different body systems; for example, the production of movement is primarily associated with the muscular and skeletal systems, regulation of hormone levels involves the endocrine system, and support and movement of the body are functions related to bones and muscles. Therefore, recognizing the integumentary system's key role in protection underscores its significance in overall bodily health and function.