Which mineral is found in the amino acids methionine, cystine, and cysteine?

Imagine you are introducing the lac operan and the trp operon to students who have never learned about it before. complete the table to compare the similarities and differences between the two operons

When in solution, a molecule that moves slowly across an artificial membrane moves rapidly across a plasma membrane. this molecule rapidly enters the cell regardless of whether its concentration is higher inside or outside the cell. using this information, which transport mechanism is most likely to be responsible for the movement of the molecule across a plasma membrane? view available hint(s)when in solution, a molecule that moves slowly across an artificial membrane moves rapidly across a plasma membrane. this molecule rapidly enters the cell regardless of whether its concentration is higher inside or outside the cell. using this information, which transport mechanism is most likely to be responsible for the movement of the molecule across a plasma membrane? active transportexocytosis

What molecules will be best used to compare different species with the exact same sequence of amino acids? why would two species have the same protein even if the molecules in question is different? (hint: transcription to translation to protein).