Hair is an important part of human anatomy and a common feature of many people. It grows on most parts of the body, including the face, ears, scalp and legs. It can be trimmed or plucked to create different styles, and it is usually dyed or colored.
The structure of human hair includes two or more layers and a layer that protects the outer surface of the hair shaft, called the cuticle. It is made of transparent, scale-like cells that overlap like shingles on a roof and is responsible for the smooth, silky feel and shine of healthy hair.
There are two types of hair: vellus and terminal (separated) hairs. The former are short, soft, fuzzy hairs that provide insulation and help keep the body warm and dry. They are found on the body’s skin, while the latter are coarser and darker in color and are found on the head.
Each hair strand has a root in the bottom of the follicle, and it is nourished by blood from tiny vessels at the base of the follicle, as well as by nutrients and water from the surrounding tissue. The roots are attached to sebaceous glands, which produce oil.
When an injury occurs, the cells in your hair follicles work with your body’s white blood cells to help heal the wound. They also help to remove dead cells and other debris that are clogging the wound.
These cells are also called apocrine cells because they secrete a hormone called apocrine gland hormone (AGH), which helps the body fight off infections and other disease. They have been shown to be involved in wound healing, as they aid the immune system’s ability to kill bacteria and other pathogens.
The hair follicle is a cylinder with a rounded bottom in the body’s skin, and it contains a papilla where the roots of your hair begin to grow out. Your hair follicle is surrounded by your scalp’s skin, so the follicle is visible under the scalp’s surface when you are looking at yourself in the mirror or when you have a shower.
Your hair follicle is shaped in a specific way that depends on the type of hair you have. The follicles that give rise to straight hair are oval-shaped in cross-section, while the follicles that produce curly hair are curved in shape.
In addition to their shape, your follicles also have special cell membranes that allow them to open and close quickly when they need to, so the hair strand can move out of the follicle without breaking. The hair follicle also has cells that help make your hair shiny and help prevent it from becoming brittle or breakable.
During growth, your hair is connected to the root in your follicle by a thin tube of cells called the dermal papilla. The papilla is a type of receptor for signals from your scalp’s nerves. When the signal is received, it triggers your hair to grow and push up from its root in the follicle.