"by lay people may not be sufficiently accurate. Hair that has been damaged by excessive exposure to chemicals is considered ""over-processed"". This results in dry, rough and fragile hair. In extreme cases, the hair can be so damaged that it breaks off entirely. The main cases of hair breakage are: Lack of moisture and oils, poor diet, stress, over processing or illness. Skin and fingernails are made of a similar type of keratinized protein as hair. That means that drips, slips and extra hair tint around the hairline can result in patches of discolored skin. This is more common with"
"Nail (anatomy) A nail is a horn-like envelope covering the tips of the fingers and toes in most primates and a few other mammals. Nails are similar to claws in other animals. Fingernails and toenails are made of a tough protective protein called alpha-keratin. This protein is also found in the hooves and horns of different animals. The nail consists of the nail plate, the nail matrix and the nail bed below it, and the grooves surrounding it. The matrix, sometimes called the ""matrix unguis"", keratogenous membrane, nail matrix, or onychostroma, is the tissue (or germinal matrix) which the nail"
"habitual locomotion on small-diameter branches. It also indicates keel-shaped nails of ""Callitrichines"" (a family of New World monkeys) is a derived postural adaptation rather than retained ancestral condition. Nail (anatomy) A nail is a horn-like envelope covering the tips of the fingers and toes in most primates and a few other mammals. Nails are similar to claws in other animals. Fingernails and toenails are made of a tough protective protein called alpha-keratin. This protein is also found in the hooves and horns of different animals. The nail consists of the nail plate, the nail matrix and the nail bed below"
"are generally expressed in particular pairs of type I and type II keratin proteins in a tissue-specific and cellular differentiation-specific manner. The keratin proteins of epithelial tissues are commonly known as ""keratins"" or are sometimes referred to as ""epithelial keratins"" or ""cytokeratins"". The specialized keratins of hair and nail are known as ""hard keratins"" or ""trichocyte keratins"". Trichocytes are the specialized epithelial cells from which hair and nail are composed. Trichocyte keratins are similar in their gene and protein structure to keratins except that they are especially rich in the sulfur-containing amino acid cysteine, which facilitates chemical cross-linking of the"
"Keratin Keratin () is one of a family of fibrous structural proteins. It is the key structural material making up hair, horns, claws, hooves, and the outer layer of human skin. Keratin is also the protein that protects epithelial cells from damage or stress. Keratin is extremely insoluble in water and organic solvents. Keratin monomers assemble into bundles to form intermediate filaments, which are tough and form strong unmineralized epidermal appendages found in reptiles, birds, amphibians, and mammals. The only other biological matter known to approximate the toughness of keratinized tissue is chitin. Keratin derives from Greek ' from '"
"and type II keratin proteins in a tissue-specific and cellular differentiation-specific manner. The keratin proteins of epithelial tissues are commonly known as ""keratins"" or are sometimes referred to as ""epithelial keratins"" or ""cytokeratins"". The specialized keratins of hair and nail are known as ""hard keratins"" or ""trichocyte keratins"". Trichocytes are the specialized epithelial cells from which hair and nail are composed. Trichocyte keratins are similar in their gene and protein structure to keratins except that they are especially rich in the sulfur-containing amino acid cysteine, which facilitates chemical cross-linking of the assembled hard keratins to form a more structurally resilient"
"weight than silk protein powders and are moisturizing to skin and hair. Silk amino acids are used in formulating shampoos, conditioner, hair treatments, bodywash, body lotions, cleansers, toners and facial moisturizers, mascara, lipstick and color cosmetics. Silk is made up of two primary proteins; a fibrous protein known as fibroin, and a sticky protein known as sericin, with the two comprising 70–80% and 20–30% of silk, respectively. Both of these proteins provide the unique functionality of silk that makes silk clothes so unique and so popular, with the production of silk material dating back to as early as 3500 BC."
"much of the animal body (e.g. muscles, skin, and hair). They also form the enzymes that control chemical reactions throughout the body. Each protein molecule is composed of amino acids, which are characterized by inclusion of nitrogen and sometimes sulphur (these components are responsible for the distinctive smell of burning protein, such as the keratin in hair). The body requires amino acids to produce new proteins (protein retention) and to replace damaged proteins (maintenance). As there is no protein or amino acid storage provision, amino acids must be present in the diet. Excess amino acids are discarded, typically in the"
"vitamin A and B results in fragile nails with horizontal and vertical ridges. Some over-the-counter vitamin supplements such as certain multivitamins and biotin may help in growth of strong nails, although this is quite subjective. Protein is a building material for new nails; therefore, low dietary protein intake may cause anemia and the resultant reduced hemoglobin in the blood filling the capillaries of the nail bed reflects varying amounts of light incident on the nail matrix resulting in lighter shades of pink ultimately resulting in white nail beds when the hemoglobin is very low. When hemoglobin is close to 15"
"protein that aids in protection. An overwhelming amount of keratin can cause disease and infection as well as some eruptions from the skin that will protrude out of the skin and lead to death. Keratin is also a waterproofing protein. Millions of dead keratinocytes rub off daily. The majority of the skin on the body is keratinized. The only skin on the body that is non-keratinized is the lining of skin on the inside of the mouth. Non-keratinized cells allow water to ""stay"" atop the structure. The protein keratin stiffens epidermal tissue to form fingernails. Nails grow from a thin"
"Noggin (protein) <nowiki> </nowiki> Noggin, also known as NOG, is a protein that is involved in the development of many body tissues, including nerve tissue, muscles, and bones. In humans, noggin is encoded by the ""NOG"" gene. The amino acid sequence of human noggin is highly homologous to that of rat, mouse, and ""Xenopus"" (an aquatic-frog genus). The protein's name, which is a slang English-language word for ""head"", was coined in reference to its ability to produce embryos with large heads when exposed at high concentrations. Noggin is a signaling molecule that plays an important role in promoting somite patterning"
"a mercaptan such as ammonium thioglycolate. Following this, the hair is curled and then 'neutralized'. The neutralizer is typically an acidic solution of hydrogen peroxide, which causes new disulfide bonds to form under conditions of oxidation, thus permanently fixing the hair into its new configuration. Proteins naturally present in the body can contain crosslinks generated by enzyme-catalyzed or spontaneous reactions. Such crosslinks are important in generating mechanically stable structures such as hair, skin and cartilage. Disulfide bond formation is one of the most common crosslinks, but isopeptide bond formation is also common. Proteins can also be cross-linked artificially using small-molecule"
"food through the intestines. Additionally, fiber, perhaps especially that from whole grains, may help lessen insulin spikes and reduce the risk of type 2 diabetes. Proteins are the basis of many animal body structures (e.g. muscles, skin, and hair) and form the enzymes which catalyse chemical reactions throughout the body. Each protein molecule is composed of amino acids which contain nitrogen and sometimes sulphur (these components are responsible for the distinctive smell of burning protein, such as the keratin in hair). The body requires amino acids to produce new proteins (protein retention) and to replace damaged proteins (maintenance). Amino acids"
"for the metabolism of methionine and cysteine in humans and animals. Disulfide bonds (S-S bonds) between cysteine residues in peptide chains are very important in protein assembly and structure. These covalent bonds between peptide chains confer extra toughness and rigidity. For example, the high strength of feathers and hair is due in part to the high content of S-S bonds with cysteine and sulfur. Eggs are high in sulfur to nourish feather formation in chicks, and the characteristic odor of rotting eggs is due to hydrogen sulfide. The high disulfide bond content of hair and feathers contributes to their indigestibility"
"higher level of force before fracture. On the other hand, soft alpha-keratins, such as ones found in the skin, contain a comparatively smaller amount of disulfide bonds, making their structure more flexible. Alpha-keratin Alpha-keratin, or α-keratin, is a type of keratin found in mammals. This protein is the primary component in hairs, horns, nails and the epidermis layer of the skin. α-keratin is a fibrous structural protein, meaning it is made up of amino acids that form a repeating secondary structure. The secondary structure of α-keratin is very similar to that of a traditional protein α-helix and forms a coiled"
"of this ability to induce secondary axis formation in frog embryos. Noggin (protein) <nowiki> </nowiki> Noggin, also known as NOG, is a protein that is involved in the development of many body tissues, including nerve tissue, muscles, and bones. In humans, noggin is encoded by the ""NOG"" gene. The amino acid sequence of human noggin is highly homologous to that of rat, mouse, and ""Xenopus"" (an aquatic-frog genus). The protein's name, which is a slang English-language word for ""head"", was coined in reference to its ability to produce embryos with large heads when exposed at high concentrations. Noggin is a"
"for the science that is associated with the study of feathers. Feathers are among the most complex integumentary appendages found in vertebrates and are formed in tiny follicles in the epidermis, or outer skin layer, that produce keratin proteins. The β-keratins in feathers, beaks and claws — and the claws, scales and shells of reptiles — are composed of protein strands hydrogen-bonded into β-pleated sheets, which are then further twisted and crosslinked by disulfide bridges into structures even tougher than the α-keratins of mammalian hair, horns and hoof. The exact signals that induce the growth of feathers on the skin"
"FOXN1 Forkhead box protein N1 is a protein that in humans is encoded by the ""FOXN1"" gene. Mutations in the winged-helix transcription factor gene at the nude locus in mice and rats produce the pleiotropic phenotype of hairlessness and athymia, resulting in a severely compromised immune system. This gene is orthologous to the mouse and rat genes and encodes a similar DNA-binding transcription factor that is thought to regulate keratin gene expression. A mutation in this gene has been correlated with T-cell immunodeficiency, the skin disorder congenital alopecia, and nail dystrophy. Alternative splicing in the 5' UTR of this gene"
"that the larvae do not confine themselves to keratin, but will also venture into the bony part of the horn. Ceratophaga vastella Ceratophaga vastella, or the horn moth, belongs to the clothes moth family Tineidae and is noted for its larva's ability to feed on keratin from the horns and hooves of dead ungulates, and occasionally on dried fruit or mushrooms. Keratin, a protein which makes up skin, hair, nails and feathers, is extremely resistant to proteolysis by the enzymes from specialised micro-organisms such as fungi and bacteria. ""Ceratophaga vastella"" is widespread in the Afrotropic ecozone. Thus far there are"
"color depends on how much of a dark substance called melanin is put into the hair as it grows. If a person has a normal set of the genes involved in making melanin, they make all the proteins needed and they grow dark hair. However, if the alleles for a particular protein have different sequences and produce proteins that can't do their jobs, no melanin is produced and the person has white skin and hair (albinism). Genes are copied each time a cell divides into two new cells. The process that copies DNA is called DNA replication. It is through"
"formation of collagen. Symptoms are similar to those of scurvy and copper deficiency, which share the common feature of inhibiting proper formation of collagen fibrils. Seeds of the sweet pea contain beta-aminopropionitrile that prevents the cross-linking of collagen by inhibiting lysyl oxidase and thus the formation of hydroxylysine, leading to loose skin. Recent experiments have attempted to develop this chemical as a treatment to avoid disfiguring skin contractions after skin grafting. Gregor Mendel is today recognized as the ""Father of Modern Genetics"" for his work with the cross breeding of pea plants (""Pisum sativum"") with different characteristics, and sweet pea"
"by precipitation from water by adjusting the pH to the required isoelectric point. Amino acids are the structural units (monomers) that make up proteins. They join together to form short polymer chains called peptides or longer chains called either polypeptides or proteins. These polymers are linear and unbranched, with each amino acid within the chain attached to two neighboring amino acids. The process of making proteins encoded by DNA/RNA genetic material is called ""translation"" and involves the step-by-step addition of amino acids to a growing protein chain by a ribozyme that is called a ribosome. The order in which the"
"by ornithine, whereas the long version is insensitive to the amino acid. Ornithine and/or arginine are key intermediates for the synthesis of urea, creatine, nitric oxide, polyamines, and protein; while proline is a major component of the connective tissue proteins, collagen and elastin. Because all three of these amino acids are a part of very significant processes, the presence of P5CS becomes an important regulator which makes sure that none of these three become deficient. Therefore, a lack of P5CS, due to mutations in the ""ALDH18A1"" gene, often leads to neurodegeneration, joint laxity, skin hyperelasticity, bilateral sub capsular cataracts, and"
"may also play a role in hair follicle formation. This gene exists in a cluster with four other paralogous genes. PADI1 Peptidyl arginine deiminase, type I, also known as PADI1, is a protein which in humans is encoded by the ""PADI1"" gene. This gene encodes a member of the peptidyl arginine deiminase family of enzymes, which catalyze the post-translational deimination of proteins by converting arginine residues into citrullines in the presence of calcium ions. The family members have distinct substrate specificities and tissue-specific expression patterns. The type I enzyme is involved in the late stages of epidermal differentiation, where it"
"glycine-proline-X and glycine-X-hydroxyproline, where X is any amino acid other than glycine, proline or hydroxyproline. The average amino acid composition for fish and mammal skin is given. First, a three-dimensional stranded structure is assembled, with the amino acids glycine and proline as its principal components. This is not yet collagen but its precursor, procollagen. Procollagen is then modified by the addition of hydroxyl groups to the amino acids proline and lysine. This step is important for later glycosylation and the formation of the triple helix structure of collagen. Because the hydroxylase enzymes that perform these reactions require vitamin C as"
"Cystine Cystine is the oxidized dimer form of the amino acid cysteine and has the formula (SCHCH(NH)COH). It is a white solid that is slightly soluble in water. It serves two biological functions: a site of redox reactions and a mechanical linkage that allows proteins to retain their three-dimensional structure. It is common in many foods such as eggs, meat, dairy products, and whole grains as well as skin, horns and hair. It was not recognized as being derived of proteins until it was isolated from the horn of a cow in 1899. Human hair and skin contain approximately 10–14%"
"naturally occurring cross-links (disulfide bonds) between protein chains in hair. Where chemical cross-links are covalent bonds, physical cross-links are formed by weak interactions. For example, sodium alginate gels upon exposure to calcium ion, which allows it to form ionic bonds that bridge between alginate chains. Poly(vinyl alcohol) gels upon the addition of borax through hydrogen bonding between boric acid and the polymer's alcohol groups. Other examples of materials which form physically cross-linked gels include gelatin, collagen, agarose, and agar agar. Chemical covalent cross-links are stable mechanically and thermally, so once formed are difficult to break. Therefore, cross-linked products like car"
"OCA2 provides instructions for making the protein called P protein which is located in melanocytes which are specialized cells that produce melanin. Melanin is responsible for giving color to the skin, hair, and eyes. Moreover, melanin is found in the light-sensitive tissue of the retina of the eye which plays a role in normal vision. The exact function of protein P is unknown, but it has been found that it is essential for the normal coloring of skin, eyes, and hair; and likely involved in melanin production. This gene seems to be the main determinant of eye color depending on"
"Neuronatin Neuronatin (Nnat) is a protein coding gene involved in mammalian brain development. It is located on Chromosome 20 in humans and is only expressed from the paternal allele in normal adults. It encodes the protein neuronatin, a proteolipid, that functions in the control of ion channels during brain development. Neuronatin begins the differentiation of pluripotent stem cells into cells with a neural fate by increasing their calcium levels. Neuronatin expression in neural tissues throughout the brain contributes to development of the nervous system. It is also expressed in several tissues outside of the brain. For example, expression in skin"
"PADI3 Peptidyl arginine deiminase, type III, also known as PADI3, is a protein which in humans is encoded by the ""PADI3"" gene. This gene encodes a member of the peptidyl arginine deiminase family of enzymes, which catalyze the post-translational deimination of proteins by converting arginine residues into citrullines in the presence of calcium ions. The family members have distinct substrate specificities and tissue-specific expression patterns. The type III enzyme modulates hair structural proteins, such as filaggrin in the hair follicle and trichohyalin in the inner root sheath, during hair follicle formation. Together with the type I enzyme, this enzyme may"
"meats, beer (from the yeast) and gravy. A moderate amount of purine is also contained in red meat, beef, pork, poultry, fish and seafood, asparagus, cauliflower, spinach, mushrooms, green peas, lentils, dried peas, beans, oatmeal, wheat bran, wheat germ, and haws. Purines and pyrimidines make up the two groups of nitrogenous bases, including the two groups of nucleotide bases. Two of the four deoxyribonucleotides (deoxyadenosine and deoxyguanosine) and two of the four ribonucleotides (adenosine, or AMP, and guanosine, or GMP), the respective building blocks of DNA and RNA, are purines. In order to form DNA and RNA, both purines and"
"SNAI1 Zinc finger protein SNAI1 (sometimes referred to as Snail) is a protein that in humans is encoded by the ""SNAI1"" gene. Snail is a family of transcription factors that promote the repression of the adhesion molecule E-cadherin to regulate epithelial to mesenchymal transition (EMT) during embryonic development. The Drosophila embryonic protein SNAI1, commonly known as Snail, is a zinc finger transcriptional repressor which downregulates the expression of ectodermal genes within the mesoderm. The nuclear protein encoded by this gene is structurally similar to the Drosophila snail protein, and is also thought to be critical for mesoderm formation in the"
"also play a role in terminal differentiation of the epidermis. This gene exists in a cluster with four other paralogous genes. PADI3 Peptidyl arginine deiminase, type III, also known as PADI3, is a protein which in humans is encoded by the ""PADI3"" gene. This gene encodes a member of the peptidyl arginine deiminase family of enzymes, which catalyze the post-translational deimination of proteins by converting arginine residues into citrullines in the presence of calcium ions. The family members have distinct substrate specificities and tissue-specific expression patterns. The type III enzyme modulates hair structural proteins, such as filaggrin in the hair"