Sulphur cycle Definition The sulphur cycle is a biogeochemical cycle that involves the movement of sulphur between rocks, waterways, and living organisms. Sulphur is one of the earth’s most prevalent elements. This non-metal is yellow, brittle, odourless, and tasteless. Sulfur is present in all protein types. Methionine, cystine, and cysteine are sulphur-containing amino acids that … Read more