Protein or the physical region of the protein that participates in chemical catalysis. In solution proteins also undergo variation in structure through thermal vibration and the collision with other molecules. Proteins can be informally divided into three main classes, which correlate with typical tertiary structures: globular proteins, fibrous proteins, and membrane proteins. Almost all globular proteins are soluble and many are enzymes. Fibrous proteins are often structural, such as collagen, the major component of connective tissue, or keratin, the protein component of hair and nails. Membrane proteins often serve as receptors or provide channels for polar or charged molecules to pass
Red hair possible the color is an effect caused by pigment degradation in the ancient paint. Judas Iscariot is also represented with red hair in Spanish culture and in the works of William Shakespeare, reinforcing the negative stereotype. Red hair Red hair (or ginger hair) occurs naturally in one to two percent of the human population, appearing with greater frequency (two to six percent) among people of northern or western European ancestry and lesser frequency in other populations. It is most common in individuals homozygous for a recessive allele on chromosome 16 that produces an altered version of the MC1R protein. Red