The linguistic root of tzaraath may mean smiting, in comparison with Arabic, in reference to a Talmudical explanation that it serves as a punishment for sin; it is quite possible that tzaraath was a general term for certain types of skin disease, rather than a particular condition, and the Talmud maintains a similar view, arguing that tzaraath referred generally to any disease that produces sores and eruptions on the skin.
Investigations of keratins extracted from wool by reduction hydrolysis and by alkaline hydrolysis showed that their chemical compositions and secondary structures were similar to original wool. The keratin isolates were similar in amino acid, Amides I and II, and secondary structure to each other and to original wool.
The length of keratin fibres depends on their water content. They can bind approximately 16 percent of water; this hydration is accompanied by an increase in the length of the fibres of 10 to 12 percent. The most thoroughly investigated keratin is hair keratin, particularly that of wool.