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
Hair removal genitalia. Forms of hair removal are practised for various and mostly cultural, sexual, medical or religious reasons. Forms of hair removal have been practised in almost all human cultures since at least the Neolithic era. The methods used to remove hair have varied in different times and regions, but shaving is the most common method. In early history hair was removed for cleanliness and fashion reasons. If the hair was cut and shaven it meant one was high class. In Ancient Egypt, hair removal was not just a fashion statement; it also served as a treatment for louse infestation, which