Skin - layer, function,glands physiology notes ( first year mbbs notes)

largest organ and primary protective barrier: Structure: The skin is made up of three layers: the epidermis, dermis, and hypodermis. The skin's thickness varies by body region, with the thickest skin on the palms of the hands and soles of the feet. Functions: The skin has many functions, including: Protection: The skin protects the body from pathogens, microorganisms, toxins, chemicals, and ultraviolet (UV) light. Temperature regulation: The skin helps regulate body temperature by constricting blood vessels in the dermis when exposed to cold temperatures. Sensory perception: The skin contains nerves in the dermis that help you feel pain, itchiness, and when something is too hot to touch. Homeostasis: The skin helps control insensible fluid loss and plays a role in general homeostasis. Composition: The skin is made up of water, protein, lipids, minerals, and chemicals. It also contains collagen, a protein that makes skin cells strong, and elastin, a protein that keeps skin flexible. Regeneration: The skin regenerates itself about every 27 days. Skin types: There are two general types of skin: hairy and glabrous (hairless).