1. Chapter 9 Cell Respiration

2. How much energy is in food?
One gram of _______ “burned” (oxidized) in presence of _______ = 3811 calories of heat energy
A _______ is the amount of _______ needed to raise the temperature of one gram of water one degree Celsius.
Kilocalorie on food labels (1 Calorie = 1000 calories)
When cells “burn” glucose, they release the _______ contained within its _______ bonds.
One gram of glucose when oxidized aerobically = 3811 calories

3. Oxygen or not? Anaerobic: “not in air” Does not require _______
Glycolysis and fermentation
Aerobic pathways in cell respiration need _______ to release _______ from food.
Krebs cycle and ETC

4. Overview of Cell Respiration
Cellular respiration is the process that releases _______ by breaking down _______ in the presence of _______.
6O2 + C6H12O6  6CO2 + 6H2O + Energy
oxygen + glucose  carbon dioxide + water + energy
Respiration Overview (3:50)

5. Study diagram on page 222.

6. The MIGHTY Mitochondrion

7. Glycolysis
Process in which one molecule of _______ is broken in half, producing two molecules of ________ _______ (pyruvate)
Energy input of ___ _____; ___ _____ produced; net gain of ___ _____.
2 ATP
2 ADP
4 ADP
4 ATP
Two advantages: speed and does not require oxygen. Cells can produce thousands of ATP molecules in just a few milliseconds. Can provide chemical energy to cell without oxygen. When a cell generates large amounts of energy from ATP, it runs into a problem. In just a few seconds, all of the NAD+ is filled with electrons and the cell cannot keep glycolysis going, thus stopping ATP production.
2NAD+
2 Pyruvic
acid 2

8. Glycolysis 2NAD+ Overview of Glycolysis (3:00)
Two high-energy _______ and ____ picked up by NAD+ to make _______
Energy in NADH carried to _____
No _______ needed and high _______ are the advantages.
It’s a form of _____ production in O2-deprived cells (muscle)
and red blood cells (no mitochondria)
2 ATP
2 ADP
4 ADP
4 ATP
2NAD+ 2
2 Pyruvic
acid
Overview of Glycolysis (3:00)

9. Fermentation
If there is no _______ present, cell will go through _____________
Cells convert _______ to NAD+ by passing high energy _______ back to _________, allowing glycolysis to continue producing a steady supply of _____.
__________ discovered it’s carried out by microbes

10. Alcoholic Fermentation
Forms _____________ and _____ as wastes.
Occurs mainly in _______ and a few other microorganisms
Causes bread dough to _______
When yeast in dough run out of _______, they begin to ferment, giving off bubbles of ______.
Small amount of alcohol evaporates.
Process explained in 1897 by German chemist Eduard Buchner – The birth of biochemistry!!!
C6H12O6 + zymase  2C2H5OH + 2CO2

11. Lactic Acid Fermentation
Regenerates NAD+ so _______ can continue.
Produced during vigorous exercise in _______
Rapid production of ATP
Lactic acid (lactate) is a _______ product
Buildup of lactic acid in _____________ causes a painful, burning sensation, but only temporarily
Broken down into ____ and _____ by liver
Moves the metabolic burden from ___________ to ___________

12. Lactic Acid Fermentation
Metabolism of Lactic Acid – The Cori Cycle

13. Lactic Acid Fermentation
Cheese, yogurt, sour cream, pickles, and sauerkraut are all produced using lactic acid fermentation.

14. Review The first step of cellular respiration is…
Where does glycolysis occur?
What occurs if there no oxygen present after glycolysis?

15. Review What are the two types of fermentation?
This type of fermentation occurs in muscle cells: ________________
Two types of phosphorylation in mitochondrion?

16. Glycolysis (review)
Process in which one molecule of glucose is broken in half, producing two molecules of pyruvic acid (pyruvate)
Energy input of 2 ATP
2 ATP
2 ADP
4 ADP
4 ATP
Two advantages: speed and does not require oxygen. Cells can produce thousands of ATP molecules in just a few milliseconds. Can provide chemical energy to cell without oxygen. One molecule glucose makes 2 molecules of pyruvate.
2NAD+
2 Pyruvic
acid 2

17. Krebs Cycle
During the Krebs cycle, _________ is broken down into CO2 in a series of ________-extracting reactions.
Occurs in the _______ of mitochondrion.
First described
by ______ _________ (1937)
aka: The Citric Acid Cycle

18. Krebs Cycle
Begins when __________ enters. One carbon from pyruvate becomes a part of _____ and is released from the cell.
At the same time, 2 _______ are combined with 1 H+ ion changing NAD+ into _____.
Next, _________ A joins the remaining 2 carbon molecules from pyruvate to form ________-CoA.
Acetyl-CoA adds its two- carbon acetyl group to a 4-carbon compound (oxaloacetate) producing ________ acid (citrate).

19. Krebs Cycle
_______ is broken down into a 5-carbon compound (alpha-ketoglutarate) and more _____ is released.
Again, 2 electrons and 1 H+ ion convert NAD+ to NADH.
Then, another carbon atom leaves in ____ as a waste product, leaving the 4-carbon compound _______ acid (malate).

20. Krebs Cycle Krebs Overview (1:55)
Following that, NAD+ picks up 2 __________ and an ____ ion and becomes __________.
Also, ADP is converted into _____.
Next, ______ picks up 2 __________ and 2 _____ ions and becomes __________
Finally, another ______ picks up 2 __________ and an _____ ion and oxaloacetate moves on to start the cycle again.
Krebs Overview (1:55)

21. Where do the products of the Krebs Cycle go?
CO2 released into the _______
ATP used for cell activities
NADH and FADH2 used to generate large amounts of ATP in the ______.

22. Review Where does the Krebs cycle take place?
Number of ATPs generated by Krebs for each molecule of glucose?
Two electron carriers generated by Krebs?
Waste product of Krebs?

23. Electron Transport Chain
The ETC uses high-energy _______ from the _______ _______ to convert 32 ADPs to 32 ATPs.
Series of carrier proteins located in inner ____________ of ______________.
So, O2 is essential for getting rid of low-energy electrons and hydrogen ions (wastes of cell respiration)
ADP

24. ________ serves as the final electron acceptor of the ETC.
High-energy _______ from NADH and FADH2 are passed from one carrier to the next.
At the end, an enzyme combines these electrons with H+ ions and oxygen to form _______.
________ serves as the final electron acceptor of the ETC.
ADP

25. Electron Transport Chain
Each time 2 ________ travel down the ETC, their energy is used to pump _____ ions across the membrane from the matrix to the intermembrane space of the ____________.
_____ ions build up in the intermembrane space, making it __________ charged and the outside __________ charged.
ADP

26. Electron Transport Chain
This imbalance of _______ between the matrix and the intermembrane space causes H+ ions to move through _____ ___________.
ATP synthase turns when this happens, converting _____ to _____
Average of 3 ATPs for every pair of _________
ETC Review (2:02)
ADP

27. Review Number of ATPs produced in ETC? Waste product of ETC?
Purpose of energetic electrons?
Location of ETC in eukaryotes? Prokaryotes?
What enables ATP synthase to produce ATP?

28. So What’s the Point?? The overall goals of the four pathways are:
a. Glycolysis: to convert ________into ______ for fermentation or _______
b. Fermentation: to produce ______ to keep _______ going
c. Krebs: to produce _______ and _______ for the _____
d. ETC: to produce large amounts of _____ for the cell

29. How much energy does a single molecule of glucose provide?
Glycolysis = 2 ATP
Krebs Cycle = 2 ATP
ETC = 32 ATP
TOTAL = 36 ATP
18 times more ATP produced with _______
Respiration extracts about 38 percent of total _______ of _______.
Remaining 62 percent released as ______

30. What happens when you need a burst of energy?
Your body contains enough _____ for only a few seconds of intense activity.
When you participate in vigorous ________, after a few seconds your body will begin to produce _____ by _______ _______ fermentation.
This type of ATP production will last about 90 _______.

31. What happens if you need energy for longer than 90 seconds?
________ respiration is the only way to generate a continuing supply of ______.
Releases ________ slower than fermentation.
Which means athletes need to train and pace themselves.
Body stores energy in muscle and other tissues in the form of the carb ___________, which can supply energy for mins.
After that, body breaks down
stored molecules, like ________ &
_______ for energy.
This is why running, swimming,
etc. are so good for weight control.
Of the carb glycogen

32. Comparing Photosynthesis and Respiration
_______ flow takes place in ________ directions
Photosynthesis ________energy; respiration ___________ energy
Cell respiration occurs in all eukaryotes and nearly all prokaryotes.
Photosynthesis occurs only in plants, algae, and some bacteria.
What happens to O2 and CO2 in plant cell?
Energy flows take place in opposite directions. Photosynthesis “deposits” energy, respiration “withdraws” energy. Photosynthesis removes CO2 and respiration puts its back.
Respiration uses the oxygen that photosynthesis releases.