In resolving a longstanding dispute, the Food and Drug Administration has announced that it will rescind approval for three of the four arsenic drugs that had been used in animal feeds at the request of the companies that market them.he issue of arsenic in food has drawn increased public scrutiny since research last year by Consumer Reports found substantial arsenic levels in rice. Arsenic residue in rice often comes from the water used to grow it, and poultry feces are widely used as fertilizer for a variety of crops.
a net-like structure in the cytoplasm of animal cells (especially in those cells that produce secretions), stack of membranes in the cell that modifies, sorts, and packages proteins from the endoplasmic reticulum. packaging products for shipping.
Catalysis- proteins are made of amino acids, which have many reactive functional groups, and can fold into different shapes that allow the formation of active sites. Defense- similar to catalysis, the chemical properties and capacity for different shapes allows proteins to be made that can attach to virtually any type of invading virus or cell. Signaling- the flexibility in protein structure allows protein activities to be quickly turned on or off based on binding to signal molecules or ions.