The Different Types of Hair and How They Work
Hair is an extremely complex substance. It covers almost every surface of the human body, protects skin, and traps particles around the ears and eyes. It can also be an expressive form of beauty. It can even regenerate after damage, without leaving scars. Let’s take a look at some of the different types of hair and how they work. In addition, we’ll learn a little about how damaged strands of hair can be repaired.
Hair grows from follicles located in the dermis. This makes it a vital biomaterial. In addition to its protective function, hair is an important biological material. Alpha-keratin, a protein found in the human body, is the primary component of hair. The structure of hair follicles is unique to mammals and is the source of most of the body’s hair. It is also the main component of skin.
In modern mammals, hair is the most common type of body armor. It is derived from the common ancestor of all mammals, the synapsids. This fossil does not show any soft tissue, but synapsids had sclerotic skin. It is thought that the earliest human hairs developed in this manner, when they were sensory outgrowths between the scales of ancestral therapsids.
The hair shaft is composed of three layers, the cuticle, the cortex, and the medulla. The cuticle consists of cells that are flat and square, and adhere tightly to the cortex cells. These cells move upwards, causing extensive overlapping of the two layers. These cells provide anchorage for the follicle and prevent dirt from entering the follicle. In addition to these functions, cuticle protects the follicle from chemical and physical damage.
Hair follicles are the most common type of hair growth. These cells divide rapidly, and then push upwards to form a hair shaft. The stem cells then die and the hair shaft sticks out above the epidermis. As the follicles continue to grow, the stem cells of the follicles divide and stick out, forming a follicle. The cells in the cuticle layer are cut off from nourishment and die, as the follicle grows toward the epidermis. These cells are then replaced with keratin, which fills the shaft.
The origins of hair are not fully understood. The earliest mammals were covered with follicles that produced both thick and thin hair. The latter was the most common type of hair, and a more common type is found on the head of a female. The roots of follicles are located deep in the skin. These roots resemble those of a follicle. The stem cells in the follicles grow into the dermis.
In contrast, hair is composed of two or three layers. The innermost layer is called the medulla and is found only in some hairs. The middle layer is the cortex and makes up the body of the follicle. It contains much of the melanin that gives hair its color. The outermost layer is called the cuticle. The cuticle consists of a single layer of cells that protects the medulla and the cortex.