Enzymes and Cellular Respiration
Review sheet
1. _________________________ are molecules that speed up the rate of a reaction.
2. _________________________ are molecules that react with the enzyme.
3. The substrate reacts with a small part of the enzyme called the __________________
_______________.
4. The model to explain how substrates and enzymes react is called the
________________ _____________ _______________ because the enzyme must
change slightly to fit with the substrate.
5. Enzymes are named for their substrates. If the substrate is LACTOSE, then the
enzymes’s name would be ______________.
6. Look at the graph below. Draw an arrow to point to the spot what shows the highest
rate of activity.
7. Look at the graph below. What is the optimum pH for pepsin?
8. What happens to an enzyme if the temperature or pH is too high?
9. Look at the graph below. What would you predict would happen to the reaction rate if
the concentration went down to 0.2? (Note: rate is in seconds)
Rate of reaction vs. concentration of enzym e
Rate of reaction
300
250
200
150
Series2
100
50
0
1
2
3
4
5
6
7
Concentration of enzym e (in drops)
10. Cellular respiration takes glucose from the food we eat and converts it into energy
units called __________.
11. The process of cellular respiration takes place in the __________________ of a cell.
12. ____________________ respiration uses oxygen, while _________________
respiration does not use oxygen.
13. In order, name the 4 phases of cellular respiration (if oxygen is present):
_______________________, ____________________________________,
_____________________________________, and
_________________________________________
14. If no oxygen is present, glycolysis is followed by ______________________.
15. NAD+ can accept H+ to become _______________.
16. FAD can accept 2H+ to become ________________.
17. Label the cristae and matrix of the mitochondria shown below.
18. Match the phases of cellular respiration to the parts of the cell/mitochondria they
occur within.
Glycolysis
Inside mitochondria/cristae
Transition reaction
Outside mitochondria/cytoplasm/.cytosol
Citric acid cycle
Inside mitochondria/matrix
Electron transport system
19. During which phases of cellular respiration is ATP made?
20. Each NADH and FADH2 will travel to the electron transport system. Each NADH is
worth _______ ATP, and each FADH2 is worth ______ ATP.
21. Use #20 to calculate the amount of ATP made during the last part of cellular
respiration:
Part 1 – 2 NADH  ___________ ATP
Part 2 – 2 NADH  ___________ ATP
Part 3 – 6 NADH  ___________ ATP
2 FADH2  ___________ ATP
Total ATP = ___________
22. Why do your muscles burn during intense exercise?
23. Cellular respiration takes glucose and oxygen and gives off ______________ and
______________ along with ATP.