Biological catalysts are protein molecules which 1. speed up a chemical reaction 2. remain unchanged after reaction 3. function optimally at 37 deg C. 4. do not have an enzymatic activity Select the correct answer using the code given below.

Enzymes are biological catalysts. Enzymes are the catalysts involved in biological chemical reactions.

A fundamental task of proteins is to act as enzymes—catalysts that increase the rate of virtually all the chemical reactions within cells.

A catalyst remains chemically unchanged itself at the end of a reaction.

Each enzyme has a temperature that it works optimally in, which in humans is around 98.6 degrees Fahrenheit, 37 degrees Celsius –the normal body temperature for humans.