Topic 8.2 HL Respiration Study Guide
Address the below Assessment Statements
□ Outline the process of glycolysis, including phosphorylation, lysis, oxidation and ATP formation. 2 In the
cytoplasm, one hexose sugar is converted into two three-carbon atom compounds (pyruvate) with a net gain
of two ATP and two NADH + H+.
□ Draw and label a diagram showing the structure of a mitochondrion as seen in electron micrographs.
□ Explain aerobic respiration, including the link reaction, the Krebs cycle, the role of NADH + H+, the electron
transport chain and the role of oxygen.
o In aerobic respiration (in mitochondria in eukaryotes), each pyruvate is decarboxylated (CO2
removed).
o The remaining two-carbon molecule (acetyl group) reacts with reduced coenzyme A, and, at the
same time, one NADH + H+ is formed.
o This is known as the link reaction.
o In the Krebs cycle, each acetyl group (CH3CO) formed in the link reaction yields two CO2.
o The names of the intermediate compounds in the cycle are not required.
o Thus it would be acceptable to note: C2 C4 C6 C5 + = → →, and so on.
□ Explain oxidative phosphorylation in terms of chemiosmosis.
□ Explain the relationship between the structure of the mitochondrion and its function.
o Limit this to cristae forming a large surface area for the electron transport chain,
o the small space between inner and outer membranes for accumulation of protons,
o and the fluid matrix containing enzymes of the Krebs cycle.
1. Complete the table below summarizing the events of aerobic cell respiration.
Reaction
Location
Purpose
ATP yield
Glycolysis
2
Matrix of the
mitochondrion
Convert pyruvate (3C)
to acetyl CoA (2C)
Krebs Cycle
Inner mitochondrial
membrane
Oxidative
phosphorylation
2. Label the diagram below with the correct processes, locations and compounds:
0
8.1/C3 Cell Respiration (AHL/Option content)
3. Many reactions in living things can be classified as either oxidation or reduction reactions.
These are particularly important in cell respiration and photosynthesis.
Complete the table below to compare oxidation and reduction reactions.
OXIDATION
Electrons are...
lost
Oxygen is…
Hydrogen is…
4.
Define phosphorylation.
5.
List two ways in which phosphorylation is used in cell respiration.


REDUCTION
6.
In the space below, draw a diagram to show the process of glycolysis.
Include phosporylation, lysis, oxidation and ATP formation.
7.
Explain the link reaction, including oxidative decarboxylation and conversion of pyruvate to
acetyl CoA and CO2.
8.
The link reaction produces Acetyl CoA (2C) from the input substrate (usually pyruvate).
The extra carbon is released as carbon dioxide. Acetyl CoA can also be produced from
fatty acids. When the fatty acid chain contains an even number of carbons, no CO2 is
released. How many Acetyl CoA molecules can be produced with the following fatty acids?
a. 23C
9.
b. 18C
c. 31C
Draw and label a diagram showing the structure of the mitochondrion as seen in a TEM image.
Include the inner and outer mitochondrial membranes, matrix, christae, mitochondrial DNA and ribosomes and a scale bar.
10. Complete the table below with the functions of the structures of the mitochondrion.
How is each structure adapted to help maximize efficiency of respiration?
Structure:
Function:
Adapted to increase
efficiency by:
Outer
membrane
Inner
membrane
(including christae)
Matrix
Mitochondrial
DNA and
ribosomes
Inter-membrane
space
11. What is an electron carrier?
12. List two electron carriers that are used in cell respiration.


13. State the final destination of electron carriers produced in the Krebs Cycle.
14. In the space below, draw a diagram of the Krebs cycle.
Include formation of citrate, oxidation, decarboxylation, substrate-level phosphorylation (ATP
formation) and production of electron carriers.
15. Identify compounds in cell respiration that contain:
Six carbons
Four carbons
Three
carbons
Two carbons
One carbons
Zero carbons
16. Annotate the diagram below with the stages of the electron transport chain and oxidative
phosphorylation. Include generation of a H+ concentration gradient in the inter-membrane space,
movement of electrons, oxidative phosphorylation by ATP synthase, use of O2 as the terminal electron
acceptor
17. In
the
space
below, using the term ‘chemiosmosis’, describe how ATP synthase works.
18. Name (with reasons) three tissues in the body that contain high numbers of mitochondria.
Tissue
Reason
Muscle
19. Explain why high levels of lactic acid might be found in an athlete’s blood test, post-exercise.
20. Explain why ATP yield in aerobic cell respiration is so much higher than in anaerobic
respiration. (Long answer question – think about knock-on effects of reduced O2). 8 marks
Link question:
21. Draw and annotate sketch graphs of the effects of the following variables on rate of respiration –
temperature, CoA concentration, pH.
Interesting reading:
 Nobel prizewinners: Krebs and Lipmann:
http://nobelprize.org/nobel_prizes/medicine/laureates/1953/