Download UNIT 3 CELLULAR RESPIRATION PROBLEM SETS SPRING 2007

UNIT 3 CELLULAR RESPIRATION PROBLEM SET (REQUIRED)
HW 3-1 - OVERVIEW OF BIOENERGETICS AND CONTROLLED REDOX
REACTIONS
1) Cellular Respiration and Photosynthesis
A) What is the major purpose of both cellular respiration and photosynthesis?
B) What is the overall reaction for cellular respiration? How is it linked to photosynthesis?
2) For questions 2A and 2B below, choose between the following:
I) animals only II) plants only III) both plants and animals
2A) Cellular respiration occurs in
2B) Photosynthesis occurs in
3A) What molecule is the energy coin of the cell?
3B) Approximately how many ATP/ADP molecules are present in a typical human cell?
3C) Approximately how many times is a given ADP molecule recycled to make ATP each
minute?
3D) Given your answers to 3B and 3C what can you conclude about our bodies demand for
ATP? (FYI: Your body contains approximately one hundred trillion cells).
3D) List 3 types of work that cells need to carry out in the cell.
3E) List two ways that ATP is synthesized in cells and briefly explain each process.
4) OXIDATION AND REDUCTION REACTIONS
4A) Fill in the blank
Not all redox reactions involve the complete ______________ of electrons; some change
the degree of electron _____________ in _______________ bonds. Redox reactions release
energy when electrons move ____________ to more ___________________ atoms.
4B) Select the correct word choice that completes the sentence.
i) Oxidation often involves (gain or loss) of oxygen and (gain or loss) of hydrogen.
ii) Reduction often involves (gain or loss) of oxygen and (gain or loss) of hydrogen
5) For each pair of species below, indicate which is more oxidized and which is the more
reduced form. Also indicate which species has higher energy and which has lower energy.
(IMPORTANT HINT: For biological molecules, More H’s and fewer O’s = more reduced and
therefore higher energy)
A) NAD+ vs. NADH
C) CH4 vs. CO2
B) FAD vs. FADH2
D) C6H12O6 (glucose) vs. CH3COCOO- (pyruvate)
E) CH3COCOO- (pyruvate) vs. CH3CHOHCOOH (lactate)
6) What is the role of NADH and FADH2 in cellular respiration?
7) Thermodynamics and kinetics, combustion of glucose vs. cellular respiration.
A) How does the AMOUNT of heat energy released compare for the combustion of
glucose vs. oxidation of glucose via cellular respiration?
B) How does the RATE of heat energy release compare for the combustion of glucose vs.
oxidation of glucose via cellular respiration?
HW 3-2 ANAEROBIC RESPIRATION
1) List the energy- investment, energy payoff and net reactions for glycolysis.
2) Why is less ATP produced in fermentation than in aerobic respiration?
3) Complete the following table:
Process
Alcohol Fermentation
Where it occurs
Inputs
Products
Lactic Acid
Fermentation
4A) Is ATP produced DIRECTLY when during alcohol or lactic acid fermentation?
4B) What molecule is regenerated during alcohol or lactic acid fermentation? Why is this
regeneration of this molecule critical to continued production of ATP in the cell?
HW 3-3 METABOLISM OF FATS AND PROTEINS
1A). How is energy (ATP) produced from fats and proteins?
1B) What molecule is the common key entry point into the Kreb’s cycle for catabolism of
proteins, carbohydrates and fats?
1C) A fatty acid has a formula of C18H35O2 . How many acetyl CoA molecules could be
produced from this fatty acid? Explain.
2A) Which enzyme is the most important control enzyme in cellular respiration of glucose?
(Recall that pathways are typically regulated at first steps (entry steps) or energy requiring steps).
2B) For each of the following molecules, indicate whether the molecule acts as an allosteric
inhibitor or activator of phosphofructokinase.
A) ATP
B) AMP
C) citrate