Search results
Results from the WOW.Com Content Network
The medulla is the innermost layer of the hair shaft. This nearly invisible layer is the most soft and fragile, and serves as the pith or marrow of the hair. Some mammals don't have a medulla in their hair. The presence or absence of this layer and the characteristics of the medulla can aid taxonomists in identifying what taxa a hair comes from.
Diagram of the hair shaft, indicating medulla (innermost), cortex, and cuticle (exterior.) Anatomy of hair. The cortex of the hair shaft is located between the hair cuticle and medulla and is the thickest hair layer. It contains most of the hair's pigment, giving the hair its color. The major pigment in the cortex is melanin, which is also ...
The hair follicle is an organ found in mammalian skin. [1] It resides in the dermal layer of the skin and is made up of 20 different cell types, each with distinct functions.. The hair follicle regulates hair growth via a complex interaction between hormones, neuropeptides, and immune cells
Hair exists in a variety of textures. Three main aspects of hair texture are the curl pattern, volume, and consistency. All mammalian hair is composed of keratin, so the make-up of hair follicles is not the source of varying hair patterns. There are a range of theories pertaining to the curl patterns of hair.
In mammalian outer hair cells, the varying receptor potential is converted to active vibrations of the cell body. This mechanical response to electrical signals is termed somatic electromotility; [13] it drives variations in the cell's length, synchronized to the incoming sound signal, and provides mechanical amplification by feedback to the traveling wave.
The hair cuticle is also known to contain anteiso-18-methyleicosanoic acid which contribute to the hydrophobic properties of hair. [5] [4] Diagram of the hair shaft, indicating medulla (innermost), cortex, and cuticle (exterior) While the cuticle is the outermost layer, it is not responsible for the color of the hair.
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
Trichohyalin is highly expressed in the inner root sheath cells of the hair follicle and medulla. [11] It was also detected in the granular layer and stratum corneum of normal epidermis, [12] newborn human foreskin epidermis, the hard palate, in the nail matrix, the filiform papillae of dorsal tongue epithelium and in rodent forestomach.