Cellular Energy: Cell Respiration

Question 1

Organisms make energy from…

Answer 1

Glucose (C6H12O6)

Question 2

Examples of cellular energy

Answer 2

ATP, NAD, FAD

Question 3

Exergonic reactions

Answer 3

They release energy. More energy is released in reactants than products.

Question 4

Endergonic reactions

Answer 4

They consume energy. More energy is stored in the products.

Question 5

How is ATP recycled?

Answer 5

ADP (DP=diphoshphate) gains a phosphate to become ATP (TP=triphosphate). ATP diffuses through cell for energy and breaks back down into ADP.

Question 6

What is the first step of cell respiration (both aerobic and anaerobic) and where does it occur?

Answer 6

Glycolysis; cytosol/cytoplasm.

Question 7

What is the main difference between anaerobic and aerobic respiration?

Answer 7

Anaerobic-no oxygen present. Aerobic-glucose is broken down with oxygen.

Question 8

What does the glucose break into during glycolysis?

Answer 8

Glucose becomes two 3-carbon molecules called pyruvate.

Question 9

Where does anaerobic respiration take place? Aerobic?

Answer 9

Anaerobic=cytosol, aerobic=mitochondria.

Question 10

What type of energy is a by-product of cell respiration?

Answer 10

Heat energy.

Question 11

What is the activation energy required for glycolysis?

Answer 11

2 ATP.

Question 12

How much ATP do the following yield?
Glycolysis
Krebs cycle
Electron transport chain

Answer 12

Glycolysis=2 ATP
Krebs cycle=2 ATP
Electron transport chain=32 ATP

Question 13

What are the products and reactants associated with combustion and/or cell respiration?

Answer 13

Reactant: O2. Products: CO2, light energy, heat energy.

Question 14

What do these stand for: ATP, ADP, AMP

Answer 14

ATP=Adenosine TRIphosphate, ADP=DIphosphate, AMP=MONOphosphate.

Question 15

How do you get the energy to stick an extra phosphate onto ADP or AMP? (Hint: A bond is broken.)

Answer 15

The bond on an O2 (oxygen) molecule is broken, which releases energy.

Question 16

Cell respiration equation

Answer 16

C6H12O6+6 O2 (mitochondria+enzymes—>) 6 CO2+ 6 H2O+ 36 ATP

Question 17

Summarize glycolysis.

Answer 17

10 steps total. Occurs in cytosol, requires 2 ATP to start, glucose is split into 2 pyruvate and 2-4 ATP. Net ATP gain: 0-2.

Question 18

Glucose, which is a…carbon compound, splits into …pyruvate, which is a…carbon compound.

Answer 18

Glucose=6 carbon, splits into 2 pyruvate (3 carbon).

Question 19

After becoming pyruvate, what two paths can glycolysis follow for the next step? (Anaerobic respiration)

Answer 19

Yeast fermentation, producing alcohol and CO2 or homolactic fermentation, producing lactic acid.

Question 20

Two examples of yeast fermentation:

Answer 20

Making bread, making wine.

Question 21

How do you make wine?

Answer 21

Grapes are the glucose source. Yeast fungi are the cells that do the fermentation. There is little to no oxygen (anaerobic). Carbon dioxide is released. A maximum of 12% alcohol (yeast waste) is produced, because alcohol kills off the yeast at 12%.

Question 22

How do you make bread?

Answer 22

The sugar and flour are the glucose sources. The yeast creates CO2, causing air pockets, making the bread rise. Alcohol is produced and then burned off while baking.

Question 23

Lactic acid/homolactic fermentation in muscles

Answer 23

Pyruvate from glycolysis is converted into lactic acid without producing any more ATP. Lactic acid in muscles is removed by diffusing into the blood and then filtering out the blood by the liver. It then turns back into glucose.

Question 24

Uses/examples of lactic acid fermentation in bacteria that are in milk.

Answer 24

It denatures milk proteins (low pH), curdling the milk to give it a sour flavor for yogurt, sour cream, and cottage cheese.

Question 25

Homolactic fermentation summary

Answer 25

In animals and bacteria, lactic acid in muscles, no CO2 produced.

Question 26

FADH and NADH produce...

Answer 26

ATP. (The ¨H¨ means they´re loaded.) They are proton carriers.

Question 27

What are the three major parts of aerobic respiration?

Answer 27

1. Link reaction 2. Krebs cycle 3. Electron transport chain

Question 28

Aerobic respiration is the...step. It uses...and occurs in the...

Answer 28

2nd, O2, mitochondria.

Question 29

Why are the inner membranes of the mitochondria important for cell respiration?

Answer 29

They increase the surface area. Mitochondria is a bunch of folded membrane squeezed into a small space.

Question 30

Formula for aerobic respiration?

Answer 30

2 pyruvate+ 6 O2---> 6 CO2+ 6 H2O+ 34 ATP

Question 31

Link reaction summary

Answer 31

The pyruvate is broken into two 2-carbon molecules called acetyl CoA by removing the CO2 and H from the pyruvate. NADH is produced. This happens in the mitochondrial matrix.

Question 32

Total production from link reaction

Answer 32

2 acetyl coenzyme A, 2 CO2, 2 NADH

Question 33

Krebs cycle

Answer 33

Acetyl coenzyme A (2 carbon) combines with a 4 carbon compound (oxaloacetate) to make a 6 carbon compound. By losing one CO2 molecule, this becomes a 5 carbon compound and NAD+ becomes NADH. By losing another CO2 molecule, it becomes a 4 carbon compound and turns another NAD+ into NADH. To turn this 4 carbon compound back into oxaloacetate, one ATP is produced by adding a phosphate to ADP. FAD is reduced to FADH2 and another NAD+ becomes NADH. This completes the cycle.

Question 34

For every ONE molecule of glucose that enters the Krebs cycle (including the link reaction), what is produced?

Answer 34

4 CO2, 6 NADH, 2 FADH2, and 2 ATP.

Question 35

Which step in aerobic respiration produces the most ATP? How much?

Answer 35

Electron transport chain, 32 ATP

Question 36

Explain the electron transport chain.

Answer 36

NADH and FADH2 lose electrons. The electrons move across the membrane of the mitochondrion, making charged molecules. The electricity generated from this motion connects phosphates to ADP to make ATP with the help of the pyruvate enzyme.

Question 37

Recap... | Cell respiration starts with..., which converts...to...and...ATP are produced.

Answer 37

Glycolysis, glucose, 2 pyruvate, 2 ATP

Question 38

Recap... | Aerobic respiration

Answer 38

Uses oxygen, makes 36 ATP, occurs in mitochondria, uses link reaction, Krebs cycle, and electron transport chain. Produces CO2 and H2O.

Question 39

Recap... | Anaerobic respiration

Answer 39

No O2, makes 2 ATP, occurs in cytosol, can make lactic acid or alcohol.

Question 40

1 ATP= 1...bond

Answer 40

Peptide.