Hair Hair Hair is a protein filament that grows from follicles found in the dermis. Hair is one of the defining characteristics of mammals. The human body, apart from areas of glabrous skin, is covered in follicles which produce thick terminal and fine vellus hair. Most common interest in hair is focused on hair growth, hair types, and hair care, but hair is also an important biomaterial primarily composed of protein, notably alpha-keratin. Attitudes towards different hair, such as hairstyles and hair removal, vary widely across different cultures and historical periods, but it is often used to indicate a person's personal
Outer plexiform layer not receiving a light signal. Outer plexiform layer The outer plexiform layer (external plexiform layer) is a layer of neuronal synapses in the retina of the eye. It consists of a dense network of synapses between dendrites of horizontal cells from the inner nuclear layer, and photoreceptor cell inner segments from the outer nuclear layer. It is much thinner than the inner plexiform layer, where amacrine cells synapse with retinal ganglion cells. The synapses in the outer plexiform layer are between the rod cell endings or cone cell branched foot plates and horizontal cells. Unlike in most systems, rod and