Chapter 6 Flashcards
Which of the following is a reactant of cellular respiration?,
Oxygen and Glucose
Based on the equation above, cellular respiration is an example of an exothermic reaction.,
TRUE
Heat is produced during cellular respiration. This is because no energy exchange is 100% efficient.This is an example of the second law of thermodynamics.,
TRUE
Based on the equation above, cellular respiration would be an anabolic reaction.,
FALSE
Choose ALL of the following which are products of cellular respiration:,
CO2, Water, ATP, heat
Which organelle is most involved in cellular respiration?,
Mitochondria
If a cell is making ATP under conditions where oxygen is absent, it is considered aerobic.,
FALSE
For every one glucose molecule: how many pyruvate are formed?,
2
For every one glucose molecule: how many acetylCoA are formed?,
2
How many CO2 will be formed if two acetyl groups go through the citric acid cycle?,
4
How many ATP will be formed if two acetyl groups go through the citric acid cycle?,
2
How many CO2 will be formed if one acetyl group goes through the citric acid cycle?,
2
Where does the Krebs Cycle occur?,
Mitochondria Matrix
Where in the cell does Glycolysis happen?,
Cytoplasm
Where in the cell does the Electron Transport Chain occur?,
Mitochondria Cristae
If 20 NADH molecules enter the ETC, how many ATP would result?,
60
If 20 FADH2 molecules enter the ETC, how many ATP would result?,
40
T/F Anaerobic respiration produces less ATP than aerobic respiration.,
TRUE
T/F If O2 is not present, the ETC can still occur.,
FALSE
T/F If O2 is not present, the citric acid cycle can still occur.,
FALSE
T/F If O2 is not present, glycolysis can still occur.,
TRUE
6 NADH molecules are produced from two acetylCoA molecules during the citric acid cycle
TRUE
Which metabolic pathway is common to both fermentation and cellular respiration?
glycolysis
During aerobic cellular respiration, a proton gradient in mitochondria will be generated by __________________ and used primarily for _________________.
the electron transport chain . . . ATP synthesis
When electrons flow along the electron transport chains of mitochondria, which of the following changes occurs in the intermembrane space?
pH of the intermembrane space drops
All of the following substances can be produced under anaerobic conditions except
NADH.
ATP.
lactate.
acetyl CoA.
pyruvate.
acetyl CoA
Energy for all life processes is derived directly or indirectly from the sun.
TRUE
Pyruvate is oxidized into Acetyl CoA prior to the citric acid cycle.
TRUE
Fermentation is an aerobic way of harvesting energy
FALSE
Which of the following can be broken down during cellular respiration to make ATP?
proteins.
lipids.
saccharides.
all
Humans can use lactic acid and alcohol fermentation to generate small amounts of ATP anaerobically.
TRUE
Which of the following is not involved in cellular respiration?
glycolysis
fermentation
citric acid cycle
oxidative phosphorylation
chemiosmosis
fermentation
ATP is produced and used continuously in all active cells.
TRUE
The final electron acceptor at the end of the electron transport chain is
oxygen
t/f Animals store most of their energy reserves as fats.
TRUE
Glycolysis is a(n) __________ reaction.
endothermic (anabolic)
exergonic (catabolic)
abnormal
endergonic (anabolic)
unregulated
exergonic (catabolic)
Where is ATP synthase located in the mitochondrion?
In the inner mitochondrial membrane.
Where is pyruvate formed?
in the cytoplasm
Most CO2 is released during
the Citric Acid Cycle (Krebs).
T/F? NADH –> NAD+ is a reduction.
FALSE
All of the following statements about glycolysis are true except:
- Glycolysis can operate in the complete absence of O2.
- The end products of glycolysis are CO2 and H2O.
- Glycolysis makes ATP
- Glycolysis has steps involving phosphorylation.
- The enzymes of glycolysis are located in the cytoplasm of the cell.
The end products of glycolysis are CO2 and H2O
Where is ATP synthase located in the mitochondrion?
In the Inner Membrane
Which metabolic pathway is common to both fermentation and cellular respiration?
Glycolysis
Which molecule(s) enter electron transport?
-ATP.
-CO2.
-Acetyl CoA.
-FADH2 and NADH.
-Glucose
FADH2 and NADH.
What is Oxygens primary role in cellular respiration?
Act as an acceptor for electrons and hydrogen, forming water.
How many ATP molecules (net) are produced by glycolysis?
2
T/F? The movement of electrons from one molecule to another is called a redox reaction.
TRUE
T/F? All organisms produce heat during their metabolic processes.
TRUE
Which is important for chemiosmosis?
A difference of hydrogen ion (H+) concentration on opposite sides of the inner mitochondrial membrane and the enzyme ATPsynthase.
T/F When NAD+ –> NADH it is said to be oxidized.
FALSE
T/F? 6 NADH molecules are produced from two acetylCoA molecules during the citric acid cycle.
TRUE
How many Hydrogen Ions and Electrons do NAD+ carry?
1 Hydrogen Ion and 2 Electrons.
What does NAD+ turn into when it picks up electrons and H+?
NADH
How is breathing and cellular respiration closely related?
Oxygen brought in from breathing supplies the cellular respiration cycle. The CO2 we breathe out comes from the cellular respiration cycle (2nd and 3rd steps).
Identify the reactants and products of cellular respiration.
C6H12O6 + 6O2 –> 6CO2 + 6H2O + ATP + Heat
Define and describe cellular respiration. Why must it occur?
Cellular respiration is the process of making ATP through the breakdown of glucose. The cells use ATP to drive chemical reactions and processes, and ATP is the main energy source for us.
What is the importance of NAD+ and FAD? Why is it important for NADH and FADH2 to be converted back into NAD+ and FAD.
They link to electrons and H+ ions and turn into NADH and FADH2. These then carry the electrons and H+ to the last step where they are used to produce ATP. NAD+ and FAD then go back to the start to pick up more electrons.
How do the electron transport chain and chemiosmosis work together? What is the result?
The ETC takes electrons into carrier proteins that act as pumps to create a high gradient of H+ from the matrix and into the intermembrane space. The gradient then goes into the ATP synthase where it is converted into ATP.
Identify the beginning reactant and the final product of each phase of cellular respiration.
1) Glucose –> 2 net ATP, 2 Pyruvate, 2NADH
2) 2 Pyruvate –> 2 Acetyl-CoA, 2CO2, 2NADH
3) 2 Acetyl-CoA –> 4 CO2, 2 FADH2, 6 NADH, 2 ATP
4) 10 NADH, 2 FADH+, 4ATP, 6 CO2 –> ~28 ATP
Why is oxygen necessary?
Because the last 3 steps are aerobic and require oxygen to happen. Otherwise, you would go into fermentation.
Where in the cell does each phase occur?
Glycolysis: Cytoplasm
Acetyl CoA formation: Matrix
Krebs Cycle: Matrix
ETC and Chemiosmosis: Inner mitochondrial membrane
What are the final products of cellular respiration?
~32 ATP, 6 CO2, 6 H2O
How much ATP is made at each phase?
1) 2 net ATP (4 total)
2) None
3) 2 ATP
4) 28 ATP
What are the reactants and products of both types of fermentation?
C6H12O6 –> 2 ATP + 2 Lactic Acids
C6H12O6 –> 2 ATP + 2 ethanol + 2 CO2
Why are muscles sore after strenuous exercise?
Because of the lactic acid fermentation.
Identify the step common to cellular respiration and fermentation.
Glycolysis
Describe the function of Coenzyme A
It attaches to an acetyl group to form Acetyl CoA and carries it to the krebs cycle before going to pick up more acetyl groups.
Under what situation is fermentation beneficial? When would the human body use fermentation?
When you work out and don’t get enough oxygen.
Approximately how much ATP does cellular respiration net? Fermentation?
Cellular Respiration: 32-38 ATP
Fermentation: 2 ATP
How many Hydrogen Ions and Electrons do FAD carry?
2 Hydrogen Ions and 2 Electrons.
What does FAD turn into when it picks up electrons and H+?
FADH2
What is the function of Coenzyme A? (CoA).
It picks up an acetyl group to carry it into the Citric Acid Cycle. Forms Acetyl-CoA.
What is an acetyl group?
A 2-carbon group.
Which organelle does cellular respiratoin take place?
The mitochondria.
Does cellular respiration occur in animals? Plants? Fungi? Bacteria?
It occurs in all of them.
How are photosynthesis and cellular respiration coupled or dependent on each other?
They are the inverse of each other. CO2 we exhale comes from cellular respiration, and it is the CO2 plants take in to release O2 that we inhale.
What is an autotroph?
Organism that produces its own food. An example is a plant.
What is a heterotroph?
Organism that needs to consume to produce energy. An example is a human.
Define anaerobic.
Without oxygen.
Define aerobic.
With oxygen.
Why is the third terminal phosphate bond in ATP important?
It is the bond that breaks to release energy when we need it.
Why must the energy in glucose be transferred into ATP in order for cells to use it?
It is the primary energy source for a cell and is in the simplest ready to use form for work
What is released as waste from ATP?
CO2 and H2O.
What is glycolysis?
First step of cellular respiration. Breaking glucose molecules.
Where does glycolysis take place?
In the cytoplasm.
Is Glycolysis aerobic or anaerobic?
Anaerobic.
What is the input for glycolysis?
1 glucose molecule (C-C-C-C-C-C)
What is the output of glycolysis?
2 net ATP, 2 NADH, and 2 Pyruvate (C-C-C)
What is spit off the sides during glycolysis?
2 ATP and 2 NADH
What comes off the end during glycolysis?
2 Pyruvates
What is a pyruvate?
A three carbon structure.
What is Acetyl-CoA Formation?
The second step of cellular respiratoin. Pyruvates are broken and turned into 2 Acetyl groups which then attach to coenzyme A in order to enter the CAC.
Is Acetyl-CoA formation aerobic or anaerobic?
Aerobic
What is another name for the 2nd step?
Pyruvate Oxidation.
What is an acetyl group?
A 2 carbon structure. Derived from Pyruvates. (C-C)
Where does Acetyl-CoA Formation occur
In the matrix.
What is the input for the 2nd step?
2 Pyruvates.
What is the output for the 2nd step?
2 CO2, 2 Acetyl-CoA, 2 NADH
What is spit off the sides during Acetyl-CoA formation?
2 CO2, 2 NADH
What comes off the end during Acetyl-CoA formation?
2 Acetyl-CoA
What is produced per pyruvate during Acetyl-CoA formation?
1 CO2, 1 Acetyl-CoA, 1 NADH.
How many Acetyl-CoA come from a glucose molecule?
2
How many pyruvates are formed for every glucose molecule?
2
Since pyruvate has 3 carbons, and the acetyl group only has 2 carbons, where did the third carbon go?
It is a waste that is the CO2 we breathe out.
What is the third step of cellular respiration?
Citric Acid Cycle (Krebs Cycle).
Where does CAC take place?
In the matrix.
Is CAC aerobic or anaerobic?
Aerobic.
What is the input for CAC?
2 Acetyl-CoA
What is the output for CAC?
2 FADH2, 6 NADH, 4 CO2, 2 ATP.
What is spit off the sides during the citric acid cycle?
2 FADH2, 6 NADH, 4 CO2, and 2 ATP
What comes off the end during the citric acid cycle?
O6
How many of each molecule is produced during 1 turn of the Citric Acid Cycle?
1 FADH2, 3 NADH, 2 CO2, 1 ATP
Why is Acetyl-CoA important in the citric acid cycle?
The coenzyme A drops off the Acetyl groups (C-C) into the cycle and is then able to go back and bond to a new acetyl group.
For one glucose, how many acetyl-CoA will enter the citric acid cycle?
2
How many CO2 will be formed if 2 acetyl groupd are completely broken down?
4 CO2
How many ATPs are formed during the cytric acid cycle?
2 ATP
What is the 4th step of cellular respiration?
Electron Transport Chain and Chemiosmosis
What is another name for the 4th step of cellular respiration?
Oxidative Phosphorylation
What happens to NADH and FADH2 during the last step?
They revert back to NAD+ and FAD so they can start the process over.
What is the purpose of the last step?
To produce as much ATP as possible.
Where does the 4th step happen?
In the inner mitochondrial membrane.
Is the 4th phase aerobic or anaerobic?
Aerobic
What is the input for the 4th step?
10 NADH, 2 FADH2, 4 ATP, and 6CO2
What is the output of the 4th step?
It uses the power of the H+ gradient to synthesize
What is spit off the sides during the electron transport chain?
FAD, NADH+, H+
What comes off the end during the electron transport chain?
ATP and H2O
What does the ETC consist of?
Many transmembrane proteins in the phospholipid bilayer where they are transported from one to the next.
Where does the H+ from the NADH and FADH2 go when they lose their electron?
Into the intermembrane space
What happens to the H+ after they are released into the intermembrane space?
They are pumped across the membrane into the intermembrane space by transmembrane proteins.
What happens in the intermembrane space with the H+ ions?
They create a high concentration gradient of H+ that moves to the ATP synthase.
What does the ATP synthase enzyme do?
It uses the power of the H+ gradient to synthesize ATP from ADP and Phosphate.
What happens to the electrons at the end of the electron transport chain?
They are picked up by O2 (very electronegative) and combined with H+ to form H2O.
What is the final electron acceptor?
O2
What is chemiosmosis?
Where the high concentration of H+ rush into the ATP synthase, when they rush through they make ATP.
What kind of energy does the H+ concentration hold?
Potential Energy
How many ATP are formed from one NADH?
3 ATP
How many ATP are formed from one FADH2?
2 ATP
What types of proteins are between the different chambers in electron transport chain?
Mobile electron carriers
Which step can be aerobic or anaerobic?
Glycolysis
How much ATP does fermentation produce?
2 ATP
What are the two types of furmentation?
Alcoholic and Lactic Acid
Where do both fermentation processes occur?
In the cytoplasm.
In what organism does lactic acid fermentation occur?
In animal muscle cells.
Reactants and products of lactic acid fermentation?
C6H12O6 –> 2 ATP + 2 lactic acids
In what organism does alcoholic fermentation occur?
In yeast and some bacterias.
Reactants and products of alcohol fermentation?
C6H12O6 –> 2 ATP + 2 Ethanol + 2 CO2
What does the CO2 release in alcohol fermentation do?
Causes rise in bread, used in fermentation of wine and beer, used to make some cheese.
