@doctor.asky: A blackhead forms from oxidized oil inside a pore. A blackhead begins deep inside a single pore on the skin. Each pore is connected to a tiny hair follicle and an oil producing gland that releases sebum onto the surface. Sebum normally keeps the skin soft, but when the pore becomes crowded with dead skin cells, the opening becomes narrow. This slows the movement of sebum and creates a small plug inside the follicle. The plug is made of trapped oil and compacted cells that stack up gradually. As the blockage grows, the top of the plug reaches the surface of the pore and becomes exposed to air. Sebum contains natural fatty acids that react with oxygen. When the trapped sebum touches air, this reaction changes its color. It becomes darker and eventually turns a deep brown or black shade. The color comes from oxidation, not from dirt. The rest of the plug remains lighter in color deeper inside the pore. The pore stays open during this process, which is why the dark tip is visible. The blocked material remains stuck inside and cannot escape easily, so the blackhead becomes stable and firm. Over time the oxidized tip hardens and creates the classic appearance of a blackhead that sits close to the skin surface. #science #biology
