1. Enzymes: “Helper” Protein molecules

2. Flow of energy through life
Life is built on chemical reactions

3. Chemical reactions of life
Processes of life
______________ molecules
______________ + +

4. Nothing works without enzymes!
How important are enzymes?
____________________________________________________________________
building molecules
___________________
breaking down molecules
__________________________________
“catalysts”
enzyme +
enzyme
We can’t live without enzymes! +

5. Examples
__________________ +
enzyme
__________________ +
enzyme

6. Enzymes are proteins
________________________________________________________________________
each enzyme needs to be the ___________ for the job
enzymes are named for the reaction they help
___________ breaks down ___________
___________ breakdown ___________
___________ builds ___________
Oh, I get it!
They end in -ase

7. Enzymes aren’t used up ____________________________________
used only temporarily
re-used again for the same reaction with other molecules
very little enzyme needed to help in many reactions
____________
____________
____________
____________

8. It’s shape that matters!
_______________________
________________ allows enzyme & substrate to fit
______________ ______________ ______________ ______________

9. 1 2 3

10. Enzyme vocabulary _________________ _________________________
helper protein molecule
molecule that enzymes work on
_________________________
what the enzyme helps produce from the reaction
part of enzyme that substrate molecule fits into

11. What affects enzyme action
_______________________________
correct order of amino acids
_______________________

12. Order of amino acids
_______________________________________

13. Temperature Effect on rates of enzyme activity
_________________________
greatest number of collisions between enzyme & substrate
human enzymes =
___________________________________
_________________________________
molecules move slower
decrease collisions

14. What’s happening here?!
Temperature
reaction rate
temperature

15. How do cold-blooded creatures do it?
Enzymes work within narrow temperature ranges. Ectotherms, like snakes, do not use their metabolism extensively to regulate body temperature. Their body temperature is significantly influenced by environmental temperature. Desert reptiles can experience body temperature fluctuations of ~40°C (that’s a ~100°F span!).
What mechanism has evolved to allow their metabolic pathways to continue to function across that wide temperature span?

16. pH Effect on rates of enzyme activity
____________________________________
depends on where in body
pepsin (stomach) = pH 3
trypsin (small intestines) = pH 8

17. pH stomach pepsin intestines trypsin reaction rate pH 1 2 3 4 5 6 7 8
What’s happening here?! pH
stomach pepsin
intestines trypsin
reaction rate 1 2 3 4 5 6 7 8 9 10 11 12 13 14 pH

18. For enzymes… What matters?
__________!