Which of the following statements about enzymes is true?
- Enzymes do not alter the overall change in free energy for a reaction
- Enzymes are proteins whose three dimensional shape is key to their functions
- Enzymes speed up reactions by lowering activation energy
- Enzyme are highly specific for reactions
- An enzyme like any protein has the secondary and tertiary structure.
- The energy input needed to start a chemical reaction is called activation energy
(a) All are correct (b) All except 5 (c) 5 and 6 (d) 2 and 4