Hair is a part of our body, and taking care of it is essential for maintaining a healthy and attractive appearance. There are many different kinds of hair, ranging from fine to thick and from matte to glossy. Depending on the texture of the hair, it may also be straight, curly, or coily. Understanding your hair type can help you understand how to care for it properly and style it properly.
Hair is made up of two or three layers, which are called the cuticle and cortex. In thicker hair, the cortex also contains the medulla, which is similar to the marrow in bone. The shape of the hair follicle determines its texture, with oval and circular follicles producing straight and curly hair.
Hair on the head, arms, and legs serves several functions. It protects the skull from harmful UV rays, keeps the head warm, and protects the ears from dust. It also protects the eyes from sweat and particles. It also serves as sensory input because the hair surface is more sensitive than the skin surface. While some types of hair serve a useful purpose, other types are not as functional. For example, hair in the eyebrows is important to protect the eyes from dust and sweat.
Hair is an important biomaterial, but it is not the most interesting part of the body. It consists of alpha-keratin, a protein filament that grows from follicles deep in the dermis. It can be found in most parts of the body, but it is most noticeable on some areas. Hair can be removed by shaving, trimming, or plucking.
Hair follicles are attached to a smooth muscle called the arrector pili, which contracts in response to nerve signals from the sympathetic nervous system. The follicle also serves as a source of blood for the hair. Nerves within the hair follicle are sensitive and can detect the slightest draft. The hair root then widens to form a round hair bulb. The bulb produces new hair cells.
Hair is an essential part of a number of mammals. It provides thermal regulation, protection from physical damage, and a means of signalling to other animals. It also extends the sense of touch beyond the skin. In mammals, a guard hair is responsible for giving warnings when predators are nearby. Hair also protects the eyes from sweat and dust. Polar bears, for example, use their fur to help keep warm. They also use camouflage while hunting and to protect their cubs from predators.
Hairstyles can also reveal a person’s group membership. Early hominids tended to have head hair as it protected them from harsh African UV rays. Hair that falls down on the head and shoulders would also have protected the head as it is very vulnerable at birth. The 1920s saw the emergence of bobbed hair, a popular style for female art students and flappers.