Figure 5.1.1 – Layers of Skin: The skin is composed of two main layers: the epidermis, made of closely packed epithelial cells, and the dermis, made of dense, irregular connective tissue that houses blood vessels, hair follicles, sweat glands, and other structures. region of a hair that projects above skin surface. Secondary cortex or phelloderm is parenchymatous and the cells contain chlorophyll in young stages. Lateral Root. These cells are generally thin-walled, in contrast to the cells of the cortex, lying below the surface, which ultimately may become very thick-walled. Root hair are absent. shaft. C) hair root. 26 Hair follicle stem cells reside in the upper part of the dermal sheath in the so-called bulge which is prominent in mice. The cells of the outer root sheath normally display a number of keratins, adhesion molecules, cytokines and growth factor receptors that are different from those expressed by epidermal cells. ... root hair plexus. The cells are rounded with many intercellular spaces in between. The root hairs have fundamental importance in absorption of water and nutrients and in attachment of… Read More; trees It exists within the dermis and the epidermis, the two top layers of the skin.For a helpful visual, think of the hair follicle as a vase and the hair as the stem of a flower. ... superficial covering of a hair consisting of a single layer of cells that overlap one another. Beginning at the first root hair is the zone of cell maturation where the root cells begin to differentiate into special cell types. The root has an outer layer of cells called the epidermis, which surrounds areas of ground tissue and vascular tissue. The cells in all of the layers except the stratum basale are called keratinocytes. The epidermis and its waxy cuticle provide a protective barrier against mechanical injury, water loss, and infection. A keratinocyte is a cell that manufactures and stores the protein keratin. Lateral roots are produced when cells in the pericycle, the layer of cells surrounding the central vascular cylinder, begin to divide, form additional cell layers that push through the outer cell layers of the primary root, and ultimately organize a second root meristem. Pericycles: 7. Each hair has three layers: the medulla (pronounced: meh-DULL-uh) at the center, which is soft 5. A hair follicle is a stocking-like structure that contains cells and connective tissue and surrounds the root of a hair. Long, thick pigmented hair such as scalp and eyebrow hair are referred to as A) body hair B) vellus hair C) lanugo hair ... hair root D) hairstrand. 4. Just under the epidermis forming the outermost layer of the cortex is a layer one or two cells in width called the hypodermis. The hair shaft is made up of dead cells that have turned into keratin and binding material, together with small amounts of water. All three zones are in the first centimeter or so of the root tip. 6. Various modified epidermal cells regulate The papilla contains an artery that nourishes the root of the hair. As cells multiply and make keratin to harden the structure, they're pushed up the follicle and through the skin's surface as a shaft of hair. This structure explains why we do not feel any pain whilst our hair is being cut. several cell layers thick, with intermediate filaments, keratinocytes and Langerhans cells. Endodermis is well-developed, single-layered and present in the young root but it gets crushed due to the secondary growth in later stages. The hair shaft is formed of three layers: The medulla – the deepest layer of the hair shaft, only seen in large and thick hairs. From: Encyclopedia of Hormones, 2003. Since its cell walls are heavily suberized and impermeable to water its apparent function is to keep the water and nutrients (which are absorbed in the root zone further down the root) from leaking out through the cortex. 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