For 10 points, name these chemical species that speed up a reaction but are not themselves consumed.
Palladium is a substance of this type in the Heck reaction, and one named for Raney consists of powdered nickel. An industrial process that produces ammonia uses one of these substances consisting of iron, and these substances can be poisoned when species bind to them chemically to block their active sites. The addition of these substances does not affect the value of a reaction's equilibrium constant, and they are contrasted with inhibitors, which may reduce these substances' activity. These substances in biology are called enzymes, and they work by lowering activation energy. For 10 points, name these chemical species that speed up a reaction but are not themselves consumed.
Palladium is a substance of this type in the Heck reaction, and one named for Raney consists of powdered nickel.
catalysts [do not accept or prompt on "enzymes"]